Sorry that I have only just found you. How refreshing, someone who understands what we dont! More please.

@GaryDoesSolar

Жыл бұрын

Hi Barnaby - glad to be of help! I'll keep the videos coming... :-)

There are many videos that cover this same general topic but the way you present things is outstanding. Well done. 👌👍👏

@GaryDoesSolar

Жыл бұрын

Hi Ramsey, thank you very much for the kind words! I'm touched, and will try to keep up the quality for future videos!

Best video of this type I have seen to date. Top marks!

@GaryDoesSolar

Жыл бұрын

Thank you! That's so great to hear :-)

As a newbie to solar I've enjoyed the relaxed way Gary delivers his easy to follow videos. I've leant plenty, thank you and well done Gary.

@GaryDoesSolar

Жыл бұрын

Thank you :-) Great that you're getting a lot from my videos! More coming soon...

Thank you, you've just saved me a job. The spreadsheet is precisely what I was about to create for my parents, to help them appreciate the long-term savings of adding a battery.

@GaryDoesSolar

Жыл бұрын

No worries, Mark - very happy to have helped you out 🙏😀

@Sadowsky46

Жыл бұрын

If adding a battery pays off, you might better first check why Energy consumption is so high. And whether you cannot shift high consumption to sunshine hours.

Thank you Gary for yet another outstanding video tutorial. I love the way you approach this topic even more than how clearly and calmly you present all your well thought out material!!

@GaryDoesSolar

Жыл бұрын

Thank you so much for taking the time to comment. Especially on this particular video. To understand what the payback might be does require some effort - and I think many people just won’t have the time/patience 👍🏻

Very comprehensive- thank you.

@GaryDoesSolar

Жыл бұрын

You’re very welcome, Paul 👍🏻 😀

I am just in the process of setting up a spreadsheet for exactly the same purpose. You have explained it so clearly. It would have taken me considerable time to come to the same clarity in setting up a spread sheet. Your thinking is far ahead of mine. So THANK YOU!!!!!

@GaryDoesSolar

Жыл бұрын

Oh, I don’t know if my thinking is all that much further ahead, but thanks for the compliment 😀 and I’ve very happy to have hopefully saved you some time 👍🏻

Great video Gary, everything is put in simple terms and not silly jargon. Keep them coming.

@GaryDoesSolar

Жыл бұрын

Thanks for the great feedback - will do! :-)

Excellent video Gary. I'm sure a lot of work went into that. Thank you.

@GaryDoesSolar

Жыл бұрын

Thanks Colin 😀 and you’re not wrong there! I’m trying to find ways to be more efficient going forward (editing etc.) 👍🏻

Brilliant - thank you!

@GaryDoesSolar

4 ай бұрын

Cheers for the great feedback! :-)

Love your spreadsheet, and videos. It's very useful when thinking about what type of system we want. Thanks Gary

@GaryDoesSolar

Жыл бұрын

Thanks Richard - you’re most welcome 👍🏻 😀

Brilliant videos, you explain the concepts very well.

@GaryDoesSolar

Жыл бұрын

Thanks David - I really appreciate the feedback! :-)

Phenomenal video Gary. 👍👍

@GaryDoesSolar

Жыл бұрын

Wow, David - thank you! :-)

Fantastic work and thanks for the detailed paramters and analysis!!

@GaryDoesSolar

10 ай бұрын

Cheers Andre - hope it's useful to you. Now although I used a spreadsheet in that video, I since developed a web app, which is much easier to use. Enjoy! garydoessolar.com/utilities/dailymodellingutility/

This channel is outstanding Gary. Thank you!

@GaryDoesSolar

Жыл бұрын

Great to hear! Thanks for taking the time to let me know :-) I'll keep the videos coming!

Well presented and a pleasure to watch ✨

@GaryDoesSolar

Жыл бұрын

Thanks very much. This is what I set out to do, so it's so great to hear feedback like this! :-)

Truly the best explanation and breakdown of payback that ive seen. well done.

@GaryDoesSolar

Жыл бұрын

Wow, thanks Mark - you've made my day :-)

Thanks, Gary. As a noob to solar, your videos are really informative.

@GaryDoesSolar

Жыл бұрын

Hi Craig, you're most welcome! Thanks for watching! :-)

Hi Gary, this is a fantastic tool. Thank you so much.

@GaryDoesSolar

Жыл бұрын

You are very welcome, Philippe. Thanks for letting me know 👍🏻

Gary, this is simply the best explanation I've seen of calculating the ROI and payback. Subscribed to your channel on the back for this. Thanks for taking the time to produce such an easy to follow video. We have recently invested in the solar and battery and are seeing the benefits but being able to verify that with the guide you have put together is good. And who doesn't love a good spreadsheet?!

@GaryDoesSolar

Жыл бұрын

Hi Martyn, that's very kind of you to say - thank you! And you know that they say the world's largest spreader of disinformation is Microsoft Excel!! :-) Hope you're able to get payback before long!

@MartynDews

Жыл бұрын

@@GaryDoesSolar I'm not too bother about payback personally. One can get too obsessive about these things. We saved up hard for this system and it was simple. Get almost zero interest in the back or put on the roof and get a lot more return, which we are doing right now.

Excellent video, really enjoying the relaxed and informative approach to this mind bendingly confusing subject.

@GaryDoesSolar

Жыл бұрын

Thanks Darren - great to get feedback like this :-)

Incredible video your information is amazing thanks for figuring this out and sharing it with us. I'm definitely going to setup a solar array at the house now.

@GaryDoesSolar

Жыл бұрын

You're too kind, James, but thank you! And good luck with your solar journey... :-)

A great clear concise video. You are becoming the go to source for guidance on Solar. Many thanks.

@GaryDoesSolar

Жыл бұрын

Hi Dave - you’re very kind, thank you 🙏. It certainly takes hours and hours of research, but if I can save people time, I’m well happy! 😀

Again brilliant Gary and confirms much of what I thought, but clearly and with a hood simple spreadsheet. I looked at the flux video and this version gives a good approach to applying corrections to the spreadsheet for the solar generation in winter and spring/autumn periods to give a reasonable estimate. Keep up the great work.

@GaryDoesSolar

Жыл бұрын

Thanks John - I really appreciate the feedback :-) Just to let you know, I've nearly finished a web app utility for the same, which allows different solar models depending on the time of year. Here is a link to an early release if you'd like to try: garydoessolar.com/utilities/dailymodellingutility/

nice explanation of the export offsetting the daily amount to pay to the grid

@GaryDoesSolar

Жыл бұрын

Yes, and I hear that at least one of the Octopus Energy tariffs in the UK has just doubled their export rate to 15p/kWh :-)

Thank you for this ! You are amazing ! Im hooked !!

@GaryDoesSolar

Жыл бұрын

Hi Kimo - you're most welcome! :-) I'll keep the videos coming...

So clear so helpful Thank you

@GaryDoesSolar

Жыл бұрын

Thanks Peter - very much appreciated - I'll keep the videos coming!

I wish I could put a thousand like for this video. but there is only one like button unfortunately. Thank you, Gary.

@GaryDoesSolar

Жыл бұрын

That is so very kind of you to say, Towid :-) I'll try to keep up the quality content for you!

Great video again, extremely helpful, thank you!

@GaryDoesSolar

Жыл бұрын

Many thanks, Richard! I wasn’t sure how this particular video was going to go down given it’s a little spreadsheet-heavy! 🤣

@courtmanr

Жыл бұрын

@@GaryDoesSolar Hey Gary, cell k10 in the Solar with Battery spreadsheet has a value of 0 - which I think is an error. Cheers

@GaryDoesSolar

Жыл бұрын

Ah now - it does look like an error, but actually isn't! I'll explain... I wanted the residual battery charge at 11pm to be used the following morning, so wrapped it around in the spreadsheet. Now, that immediately caused a "circular reference" error, as expected, so I decided to break the circle by zeroing out any battery charge left just before the sun came up. Not ideal, but we're kind of reaching the limit of what a spreadsheet can do! :-) Thanks for spotting though!

Well done sir!

@GaryDoesSolar

6 ай бұрын

Thank you :-)

Thanks very much for another brilliant video. Incredibly informative and yet presented in a very simple way.... Engage, Inform, Inspire 🙏

@GaryDoesSolar

Жыл бұрын

Thank you, Nic 😀 that’s very kind of you to say 👍🏻 I’ll keep the videos coming!

YESSS! VIDEO 3! Keep it up Gary!

@GaryDoesSolar

Жыл бұрын

Will do. Working on the next one now... :-)

Another great video Gary

@GaryDoesSolar

Жыл бұрын

Thanks Dan! Working on the next one now... solar diverters... :-)

What a superb series of videos covering the challenges of solar installations. Clearly explained and very professional presentation. Thank you Gary

@GaryDoesSolar

9 ай бұрын

Hi Vincent, that's very kind of you to say - thank you! It's an incredible amount of work, taking up all my free time outside of my day job, but it's comments like this that keep me going! :-)

Thanks for this, very helpful and great channel

@GaryDoesSolar

Жыл бұрын

It is my pleasure 😀 thanks for watching my videos 👍🏻

Great video again and thanks a lot for the spreadsheet. I tweaked mine a bit to include the losses across different seasons and come up with a yearly figure as well as adding a bit to include standing charge.

@GaryDoesSolar

Жыл бұрын

That's great - and exactly what I was hoping people would do... improve on the start I'd made :-)

@dreid5189

Жыл бұрын

@@GaryDoesSolar how did you get the figure for the solar model 0>1 numbers? I thought maybe from the Europa map thing on your other video but can’t get figures that make sense

@GaryDoesSolar

Жыл бұрын

I just took a daily summer profile (bell curve) from a south facing house near Oxford, UK and modelled that.

@dreid5189

Жыл бұрын

@@GaryDoesSolar do you have a link at all how to do that, or are your figures kinda ok anyway? I’m in Scotland. Can’t see anything come up doing a search

@GaryDoesSolar

Жыл бұрын

I can't find my notes where I constructed the model, but it should not matter too much that you're in Scotland - remember the '1' in the model will always be the maximum output of your array. And the sun will always rise and fall creating the same kind of bell curve 👍

Very informative video. Well done. Thanks a bunch.

@GaryDoesSolar

5 ай бұрын

You’re most welcome! 😀

Excellent video's. Very clear, simple to follow and VERY informative! Well done Gary. Sub'd and look forward to more content soon!

@GaryDoesSolar

Жыл бұрын

Thanks very much for the sub - much appreciated! :-) Next video just released...

Hi Gary, thanks for sharing. You don't need the excuse for working with a spreadsheet. Over simplifying does not help a serious user who is ready to plunge a fortune into a serious investment. Cheers.

@GaryDoesSolar

11 ай бұрын

Cheers 😀 and if you like the spreadsheet, I think you’ll really like the utility that developed from that. Try it here: garydoessolar.com/utilities/dailymodellingutility/

Thanks Gary, first time i have come across your videos. The most informative videos i have seen on the subject so well done, and considering you started in April this year and have only done 3 videos, you have done brilliantly to get 4.8K subscribers. Just goes to show you are hitting the right level of engaging content. Thanks for posting. Have subbed and am keen to watch your upcoming content. You don’t have to convince me though of the need for solar, i already have 8KW installed - 1 4kw array facing east and one 4kw facing south. Generated 991kwh in August and was gutted to miss 1 megawatt hour by 9KW. Tesla battery beings installed soon. Cheers John

@GaryDoesSolar

Жыл бұрын

Hi John, thanks for the kind words. Yeah, I'm really happy to be getting really good traction in such a short space of time :-) I set out to share the knowledge I'd learned through my own research into solar, to save time for everybody else, and I thought that if I could recover the costs for the recording equipment etc., then great! You're ahead of the game from me. I was due to have my installation back in August, but I had problems with the company I'd contracted with, so had to start again. I should have 7.6kWp in place around the end of the year (so not too much less than you're own installation). Wow - pretty much 1MWh in a month is just amazing! Hopefully you're with Octopus Energy so you can benefit from their recent 15p/kWh export announcement :-) Good luck with the Powerwall install - I guess you'll have been waiting for that for a while!

@juttley72

Жыл бұрын

@@GaryDoesSolar Hi Gary, yes i am with octopus and have been for a couple of years now with octopus go. Unfortunately, well not really, my original array (the 4kw west facing was fitted back in 2008 by the previous owners) and so i have a fit payment of £1500 per year on average. This was great for the first two years as our electricity bill was £1200 a year so we were up around £300. However that ended with the price rise which prompted me to add another 4kw in July this year and order the battery at the same time to get zero VAT on the battery. Big backlog so not being fitted until mid december. Still it has a really positive impact on our monthly bills, and adding a zappi to replace our podpoint has really helped to top up my EV rather than sending stupid amounts of export to the grid. Most days my car soakes up any export. for august I idid 1485 miles in my EV of which only £6.69 was paid in overnight charging giving me a cost of half a pence per mile. This would not have been possible with the podpoint which i regret getting as i wasted my govt grant getting it only the replace it six months later with the zappi at a cost of £1,000. Because i have a fit payment, i cannot sign up to another export scheme without giving up my FIT so i am in the position at the moment that my newest array attracts no payment for export. That said, my battery and car should resolve any export once fitted, so i am not too bothered. The main thing i want is to be off grid for as much of the year as possible barring the standing charge. I don’t have gas or oil, so my electric bill covers all my house, travel and mowing costs. I have a ride on electric zero turn mower to mow our field with is just shy of 2 acres and would otherwise cost me £100 a time to have it mowed professionally, so i top up the batteries when the sun is out and charge it for free. Sorry long winded response, but renewables definitely the way to go.

@GaryDoesSolar

Жыл бұрын

Hi John, it sounds like you're well on top of the situation. Loving the fact you've got an electric ride-on mover! :-) Yeah, the FiT scheme feels like an albatross on one hand, because you can't change anything, but you can't knock £1,500 a year! Thanks for the word up on PodPoint - I hate buying twice on anything.And I agree, I think we're all only get getting started on our renewable journeys - the world is changing (finally) and governments are finally waking up to that (even if in the UK, ministers are promoting fracking once more, likely mainly to secure future personal income post parliament)...

This is the most wondefully helpful channel, not least because you teach from basic first principles and build from there. So much of what you cover is actually applicable to many areas beyond the headline topic. Despite interest in this area for years I feel so much better informed. A properly Scottish approach! Will be using your code when we join Octopus in coming weeks.

@GaryDoesSolar

4 ай бұрын

Thank you very much for these kind words. It really helps as I get some haters from time to time. I just don't know why people could have a problem with someone who's spending 100s of hours trying to educate everyone about a really important topic, but there you are! I'm very happy to have in a small way, and thank you for thinking of me wrt using my referral code - it all helps! :-) All the best for this year!

Your presentations with a mix of technical and common sense information are very informative and easy to follow, therefore giving us guidance when deciding what kind of solar investment is good for each of us. I am really glad that your channel found me. Thank you

@GaryDoesSolar

Жыл бұрын

Thanks Richard - this is the very reason I started making these videos. I'll keep them coming :-)

@richardszyniszewski2791

Жыл бұрын

@@GaryDoesSolar 😊

Outstanding!

@GaryDoesSolar

Жыл бұрын

Thank you, Steve! 😀 really great to get such feedback!

@buddywheels

Жыл бұрын

Not at all Gary, credit where it’s due. You obviously know the subject inside out and your communication style is second to none. Splendid.

Update as of June 2023, my unit rate is currently 48.49 pence per KWH. So on your graph ( at 7 minutes) more like line number one. Thats partly why I am watching this.

@GaryDoesSolar

11 ай бұрын

Yeah, energy prices have been a bit crazy last couple of years, but it seems they’re starting to return to “normal” levels over the next year or so. I say normal, but the the UK that still means twice the price they were say 4 years ago!

Wow great video, just starting the journey.

@GaryDoesSolar

Жыл бұрын

Thank you! 😀 I’ll keep the videos coming 👍🏻

Excellent video as usual Gary. Please keep making them, we all appreciate it! One of the best youtubers for explaining solar I have come across.

@GaryDoesSolar

Жыл бұрын

Hi Rob, thanks very much! You're far too kind, but I'll take the praise!! It's really hard work making the videos but comments like this, give me a warm feeling inside! I'll keep going :-)

A super helpful video again, I wish I'd found and watched this before playing with your lovely spreadsheet, as it took me a little while to figure out what to change to cater for my E/W facing roof :) Again this is great and really helpful work, thank you so much!

@GaryDoesSolar

Жыл бұрын

Hi Chris, you're most welcome. Yeah, spreadsheets are great but the modelling is getting a little too complex now, so I made a web utility instead. See what you think:

@GaryDoesSolar

Жыл бұрын

garydoessolar.com/utilities/dailymodellingutility/

@Gelp

Жыл бұрын

@@GaryDoesSolar Thanks for the reminder. I'll try to have a go with that over the weekend, hopefully get similar results to my own, but no don't better 😊👍

As a data analyst I have to say you have some really good charts here and very well explained thank you as I have just started my solar journey with a small 3.2km system and no battery.

@GaryDoesSolar

Жыл бұрын

Thanks Philip - I'm no data scientist, so that's great to hear! :-) Great that you've taken the jump into solar, and I can see you extending your system to a battery very soon! By the way, worth looking at Octopus Energy as they have some very good export rates now (15p per kWh)!

Thanks Gary. Excellent spreadsheet and perfectly timed for me as I am currently trying to figure out my own PV + battery install. Top of my priority list is to have a system that (within reason) minimises our dependence on the grid even during the darkest winter months. That isn't to say that cost & pay-back period are completely irrelevant but they aren't my topmost priorities. However, having spoken to several local installers, most seem to want to install a 'standard' 4Kw system that doesn't exceed the 3.68 DNO 'soft ceiling'. Whilst this would comfortably cover our summer needs it wouldn't come close during the winter. We have sufficient (suitably orientated) roof space so the (relatively) marginal cost of additional panels makes sense to me.

@GaryDoesSolar

Жыл бұрын

Thanks John 👍🏻 glad I’ve been able to help you out. Worth considering SolarEdge (and maybe other inverter manufacturers) that can handle significant oversizing (e.g. an array twice that of the inverter)…

Love me a good spreadsheet. If the formulas are not too difficult, you could put them into a google sheet and share them that way. Single link will always get the latest one, you would just need to version whatever the latest is in the sheet itself

@GaryDoesSolar

Жыл бұрын

Thanks Nick - I hadn’t thought of Google Sheets, but now that you mention it - I’ll check it out - thanks!

@youxkio

Жыл бұрын

@@GaryDoesSolar Yes, Gary, and please let it "share to whoever has the link" and set it for "only viewers". @Bjørn Neyland also has available a Google Sheet with his test-drive results.

Another great video...Cheers

@GaryDoesSolar

Жыл бұрын

Thanks David - I’ll try to keep them coming 👍🏻😀

Love the presentation style. As sums make me want go and lie down in a dark room with a G&T this video was quite a tonic. The variability of the unknowns such as the opportunity cost of the initial outlay and the impact of any future gvt 'inducements ' do shift the line on the graph considerably. Pfftt!! Keep up the good work...

@GaryDoesSolar

5 ай бұрын

Thanks David 😀 that made me chuckle! Since that video was made, I now have a utility that is more advanced than the spreadsheet - worth a look!

Thanks ❤❤

@GaryDoesSolar

Жыл бұрын

You're very welcome! :-)

That is incredibly useful, thanks. And I second the request for a Google Sheets version. 👍

@GaryDoesSolar

Жыл бұрын

You’re most welcome, Stephen 👍🏻 I’m looking into Google Sheets…

This video alone got you a sub from me. Outstanding work

@GaryDoesSolar

Жыл бұрын

Thank you so much! Glad you enjoyed 😀👍🏻

Very well done. I am currently evaluating solar array for my 68 sqm flat roof with two options (centralize with Fronius string inverter and decentralize with Enphase IQ7 or IQ8). Your spreadsheet is just perfect, just have to switch to €.. Watching many of your videos. very interesting.

@GaryDoesSolar

Жыл бұрын

That's great to hear - glad to have been of some help to you in this! Take a look at my most recent video (on microinverters) - could certainly be an good option for you :-)

Great video. I did similar myself but yours has some extra features which are better than mine. I’m going to compare more closely. Thanks for your videos. They are really informative. Wish i was able to see before I bought my system.

@GaryDoesSolar

Жыл бұрын

You're most welcome! Yeah, I wish I'd got into solar years ago - but there was no-one round to tell me! Lol Now, my utility won't be perfect - attempting to model real-world systems to any kind of high-degree accuracy is a potential road to insanity - but hopefully it's good enough for folks to make informed decisions.

@UntrainingUltrarunner

Жыл бұрын

@@GaryDoesSolar agreed. I found it a real can of worms and hard to get quality information before I got mine installed. Luckily I think I’m alright but I think going again I’d have gone for even more panels. Plus a bigger inverter even if I had to wait for DNO

Oh My Goodness. That spreadsheet is absolutely brilliant. I am ashamed that I didn't think to analyse this issue in the same way, but you have nailed it! Thank you so much Gary for all your effort and for sharing it with us lesser minded individuals. I am having so much fun playing around with this fabulous tool! I also appreciate you answering my question on your last video. It seems that even Ecobubl has now announced that they are not currently taking any more solar PV/battery enquiries, so well done for getting your foot in the door!

@GaryDoesSolar

Жыл бұрын

Hi Ben, so great to hear you're getting a lot of value from the spreadsheet :-) and sorry about the situation with Ecobubl - it's just so crazy these days with the demand for solar. I hope you're able to find a good installer before long!

Hi Gary... fantastic job on explaining the intricacies of the variables related to solar systems. I noticed a grammatical error in your spreadsheet and was thinking about letting you know - but then when you mention "if you see any errors in my spreadsheet, let me know..." so here it is: you have a paragraph of "disclaimers" on the left hand side. You actually have the word "errors" back-to-back, so you can remove one of those words and all will be well. Greg (garden grove, CA)

@GaryDoesSolar

3 ай бұрын

Thanks for raising this - I think I need to overhaul that webpage anyway, so I'll fix that when I do - cheers! :-)

I've just had a PV and battery system installed. 12kWp PV with 7 kWh battery storage. Just ordered an additional 3.5kWh battery for the system. Was interested in the effect on the payback period with the 3rd battery. I will feed data into your spreadsheet. Thanks for the excellent videos.

@GaryDoesSolar

Жыл бұрын

Hi Harry, thanks for the kind words - and that's a very good sized system you have there! Worth looking at Octopus Energy if you're not already with them, given they've just raised export price to 15p per kWh :-)

You are the best source of impartial advice out there on the web for newbies like me. Love the Flux web calculator, with a 5 kWp array and a 10 kW battery system it's suggesting an annual income of >£1500 pa !!

@GaryDoesSolar

Жыл бұрын

Hi Ray, thanks for the kind words. Re. the Flux calculator, remember that not every day will be sunny, and as you head towards the winter later in the year, your production will drop (the "Maximum Array Output" field is not your array size, but the maximum output you could expect for the time of year (e.g. winter will be say 20% of summer) - but yeah, you should still be able to make a nice profit :-)

This panel can put out close to 100 watts kzread.infoUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.

@GaryDoesSolar

9 ай бұрын

?

Thanks for the great video and web calculator Gary. It would be interesting to see what happens as you add extra batteries to an existing setup - this is the situation I'm in with a PV installed in 2016, 3.6 Kwh DC battery/inverter in 2017 on FIT and now I'm considering adding a MyEnergi Libbi (I already have a Zappi and Eddi) for addition battery storage.

@GaryDoesSolar

Жыл бұрын

Thanks for the great feedback, Cliff. You raise a really good question, and I'm not sure the answer in fact. If the second battery was made by the same manufacturer and simply an extension of the DC-coupled connection, then I'd expect the inverter to manage it without problem. It's not likely to be possible to mix battery manufacturers in a DC-coupled setup, and if the new battery is AC-coupled, there might be a battle of wills between the two batteries... Maybe others can comment...

Gary... excellent videos and the spreadsheet has saved me a great deal of time and effort... its made me realise that for my circumstances reducing installation size (and therefore cost) from the optimum, within reason, does not significantly impact savings. One comment on the spreadsheet... the battery discharge calculation within the battery level formula seems to reduce the figure by the discharging losses %, rather than increasing it, assuming I am understanding the meaning of discharge losses %.

@GaryDoesSolar

Жыл бұрын

Hi Kevin - great to hear the spreadsheet has been helpful. It's only when you really get into the numbers that you see things like that. Yes, I think you're right - the discharge formula seems to be wrong, and thinking about it - it's going to be a tricky one to fix! Lol I'll try to resolve this in the next version... :-)

@GaryDoesSolar

Жыл бұрын

Ok, I think I've sorted it - see version 1.02 :-) The good news is that because the default discharge loss is only 3%, it didn't affect the calculations by much at all in previous versions.

@kevinmccormack7169

Жыл бұрын

Gary... just to repeat... thanks for an excellent spreadsheet, it will help me enormously negotiate suppliers away from their "one size fits all" 4Kw with battery offering !

Thanks Gary for an excellent summary of how the use of solar could significantly reduce the cost of electricity for home users. I have a 6.6 kWh solar system and have been considering adding at least a 10 kWh battery to it, but the cost in Australia is still too high. I estimate the ROI would take about 10 years (the warranty period for the battery).

@GaryDoesSolar

Жыл бұрын

Hi David, thank you for the very nice feedback :-) Yeah, battery costs have increased quite a bit over the last 2 years, but with EV demand increasing, I'm expecting economies of scale, and of course newer battery technologies, to start driving those prices down again. Hopefully, in the next year or two, the ROI will drop quite a bit! Let's see...

Thanks Gary for the spreadsheet. Please could you also put a model for winter solar production?, Also, it would be quite useful to include a model for winter where we could charge battery using off-peak tariff

@GaryDoesSolar

Жыл бұрын

You're welcome. Now, the model for winter is basically the same as summer, but with less hours of sun. It would still go from 0 to 1. I'm quite busy with work at the moment, but I'll try to add this at some point.

Absolutely love the breakdown on systems and costs. Oh my, that is one impressive bill to cap electricity prices! that has to be several hundred million pounds...... Having a look at the differences between France and Germany on power mix and $/kW: France has about 10% green, 70% Nuclear versus Germany about 29% green, 12% Nuclear; French domestic electricity prices are half that of Germany; Germany also has a very high retail $/kW versus wholesale price (I think this means Domestic vs Manufacturing) France gets about three billion euros per year from electricity exports. Further to this, France has very low Greenhouse gas emissions for electricity generation, but Germany produces more Greenhouse gases than any other EU country. So, I know what I'd like my electricity to cost. Going 'green' has hidden costs in the building and maintenance of your electricity grid as well. At night, nuclear and hydro keep working, but solar and wind are fickle beasts.

@GaryDoesSolar

Жыл бұрын

Hi there - thanks for the kind words. Yeah, the UK is is a bad place at the moment with regard to energy policy. The estimates are it will cost in the order of £150bn over the next 2 years just too subsidise the increased energy costs for consumers. I'll be making a video on all of this soon, including coverage of nuclear and hydro... :-)

I love your clear presentation style, calm voice and tidy diagrams. You should be a university lecturer! ;-) Interesting that your spreadsheet is focused on hourly consumption. I get that it's necessary because of solar hours/day and day/night cost, but the monthly variations are massive when it comes to solar generation and winter energy consumption. e.g. 6x as much from solar during summer months compared to December, and (for me) 2.5x electricity consumption in winter compared to summer. Maybe a more zoomed-out spreadsheet that looks at months instead of days to account for such seasonal differences and provide overall annual cost/saving statistics? Your energy bill shows how much you consume during the day and night rate (separately) so with some assumptions on usage an annual estimate could be obtained.

@GaryDoesSolar

Жыл бұрын

Thanks Gary - it’s great to get feedback like this! 😀 I don’t think the good university lecturers get paid enough, and maybe global video platforms like KZread are the way forward for education - not replacing face to face interaction, but providing a means for those who can articulate knowledge well to get paid well as a result. Now, you raise a good point about the spreadsheet - it’s focussed on the hours of the day because that’s where the interactions between power consumption, solar generation and inverter/battery capability can make or break your savings potential. That said, I am indeed working on something wider than that - more on this soon 😎

Very good, nice ....😊😊😊

@GaryDoesSolar

Жыл бұрын

Hi Jovan, thank you! :-)

Great video again Gary, very informative! Have you had much feedback on solar tiles in UK; I have a new build and thinking of using solar tiles. Nulok have a system I’m considering. Thanks…

@GaryDoesSolar

Жыл бұрын

Hi Andrew - thanks! No, as yet I’ve not looked into that technology in any detail. Suffice to say though, it is certainly worth considering for a new roof or roof replacement. All the best with whatever approach you decide to take! 👍🏻

Very well presented, simple and understandable. The spreadsheet is great too. If your a newb like me. I recommend watching Gary's other videos 'A beginner's Guide to Solar' and 'How to choose Solar Wisely and Avoid costly mistakes as well. Many thanks. 5*****

@GaryDoesSolar

Жыл бұрын

That's really kind of you to say - thank you! :-)

@GaryDoesSolar

Жыл бұрын

Btw, there's a web app version of the spreadsheet available now if you'd like to try: garydoessolar.com/utilities/dailymodellingutility/

Excellent clear and concise and I'll use your wisdom go calculate my costs for my solar and battery journey. Thanks your effort and knowledge is greatly appreciated.

@GaryDoesSolar

Жыл бұрын

It is all my pleasure - very happy to help you out 👍🏻 It’s hard work but comments like this make it all worthwhile 😀

Thanks Gary. A really well put together presentation which I enjoyed (again!). Having now used your spreadsheet, solar with battery tab, for an upcoming installation I can see that a larger battery than what Ive been specified would lower my import costs. However what I dont know is what month or season the solar model generation numbers are based upon. If for example they are based upon the summer season then maybe a larger battery wouldnt improve the savings significantly as during the winter I might struggle to fully charge the larger battery. Are you able to clarify the month or season for those values? Many thanks and I look forward to your future videos. Ive also shared them with friends and family who are also considering the solar route.

@GaryDoesSolar

Жыл бұрын

Hi Ron, thanks for the great feedback! :-) Now, you raise an important point! The sun model I used was a summer one! Which means, in winter the number of hours the sun is out will be significantly reduced (the model is normalised so the level of solar depends only on the maximum output of the array, which you'll be reducing for winter (e.g. to 30% of summer) anyway. This can of course be fixed by using separate solar modals for each season (or even each month) but the problem is, that we're really pushing the boundaries of a spreadsheet now. The good news is that I'm working to solve this... More soon... :-) Thanks for highlighting - I really appreciate it!

Just watched all your content Gary - Absolutely brilliant! Is there any chance of a version of your spreadsheet in an older version of Excel or Google sheets, please?

@GaryDoesSolar

Жыл бұрын

Thanks Rob - it’s great to get feedback like this. Now, unfortunately I don’t have a lot of time, but this might help you: support.google.com/docs/answer/9331167?hl=en-GB

*** For those of you interested in using the spreadsheet, I've created a much easier to use utility here: garydoessolar.com/utilities/dailymodellingutility/ - see what you think! 😃 The more astute of you will see that in cell K10 of the "Solar with Battery" sheet is '0' rather than a formula. This looks like an error, but actually, it's a little trick - I'll explain: Rather than managing the battery level from hour 0 until hour 23, I recognised that in real-life there would be charge in the battery at hour 23 that could be used the next day (hour 0 and so on) so I essentially loop from hour 23 back to zero. But in order to void the circular reference, I intentionally zero-out the battery charge at hour 6 - just before the sun comes up (the value of cell K10 is deliberately set to 0. IMPORTANT: The side effect is that if there was still charge in the battery at hour 5, this just gets lost. Trying to model non-trivial real-world scenarios in a spreadsheet is a constraining experience! 🙂

@PaulGodbehere

Жыл бұрын

Loving all 5 videos so far, thank you. Do you have any plans to release a revised version of your spreadsheet which can track both solar generation & battery storage, but also combining them with variable electric tariffs to charge the battery off-peak if your solar array isn't very large.

Hey Gary, you are brilliant! From all the videos I’ve watched you are the most informative and well spoken person. Congratulations on your success. Want to ask you a question maybe asking you the same every day. Can you help me out decide what to choose as materials and equipment, and who to use as installer? Talking about house in Hornchurch/ London. Very best of luck, Regards Biser

@GaryDoesSolar

Жыл бұрын

Hi Biser, thanks for the lovely words! It's a lot of work making these videos, but comments like yours make it all worthwhile :-) Now, your question is a good one - and there is no single answer as it very much depends on your property, electricity usage, if you have (or intend to have) an EV etc. Unfortunately, l'm not really in a position to provide such individual advice, (not least because of potential liability issues - even if that advice is given free - such is the world today). You're best to speak directly to an installer about that, or post a comment onto a solar forum (e.g. this one in the UK: facebook.com/groups/2197329430289466) Good luck with your solar journey!

Gary thank you very much indeed. Your thorough and really helpful spreadsheeting has really chrystalised what I instinctively felt were the necessary considerations. I really like the Octopus approach to smoothing out peaks of demand locally. I have the real estate for a sizeable array, and I'm happy to design and fit the entire system for final inspection and connection by an approved sparkie but I don't think our current energy rules will allow that sensible approach. So instead I've approached the local Octopus approved fitters but they are quoting eyewatering costs (£27k) and of course throwing micro inverters/optimisers at every panel for my unshaded roof. I'm considering buying and fitting the panels and battery and then asking Octopus (installers) to come in and finish it... it would be great if you had any advice in this area. In the meantime thank you again from all of us!

@GaryDoesSolar

Жыл бұрын

It is my pleasure to help you out - thanks for taking the time to comment. Wow, £27K is an eye-watering sum! I'm avoiding offering advice to people as there are liability concerns (even if the advice is given free), take a look at my latest video published today. There's more in there about optimisers and array considerations in general. Then have a listen to the podcast I was interviewed in as that might have other useful input to help with your decision-making... All the best!

Very informative video. I think I’ll have to watch it a couple of times for everything to sink in, lol. I’m still waiting for companies to get back to me for quotes. I’m financing the install so at least for the first winter I’ll be worse off, but going forward over the long term I should be better off. If that even makes sense?? 😂

@GaryDoesSolar

Жыл бұрын

Thanks for the kind words 🙏 yes, it’s quite a leap, financially - and that’s why I made this video in fact, to help people work out the numbers themselves, to satisfy them in terms of risk mitigation, especially against bank loan. Knowledge is always power, but it does come with effort - all I’m doing is making the effort a little easier, hopefully.

Hello Gary, thank you for your video(s). I live 300 km north of Toronto. I would love to go off-grid, but that is not economically feasible. However, I feel that net metering is getting closer. In Ontario, our electricity is significantly cheaper than what you describe in the UK. You talk of L0.40/ kWh. I am not sure if that is including any fixed charges such as 'customer fees' and so on. Converting the currency this would reflect a commensurate rate of about $0.68 CAD/kWh. With basic electricity rates of 10.3c/kWh and perhaps 23c/kWh when the ancillary charges are added, rates such as those you suggest would be the grounds for the fall of numerous governments and other civil mayhem! There seems to be a sense in the general population that the basic needs of society should be as cheap as possible so we can buy toys and have big houses whilst the debt for not paying proper amounts is passed on to the unborn. I feel that there is a lot of social inertia behind this. We are a free, capitalist society with reasonably priced post-secondary education. So, folks should avail themselves of it and make enough money that such things can be paid in full. Rant over. The point is that with such low rates, those of us who might want to switch even it is for 'entertainment' cannot find a reasonable financial reason for doing so, which is depressing as our planet sickens. That being said, I wanted to commiserate with you over your modelling. First let us assume that the array is on a roof top and bears the inclination of the roof top. Furthermore we need to ascertain the azimuth of the roof with the solar. While may will be 'south-facing' the true direction (azimuth) is not going to be exactly south in most cases. For example, much of our Ontario roads were laid out in the days of magnetic compasses. Now perhaps they did know of magnetic declination or did not care, but our 'north' pointing roads are often pointing at 348 or 350 deg true. This will affect solar generation. 1. So for the array I describe, it will not generate anything when the sun is behind it, so the longer days of summer are not rewarded in this area other than the sun being at a higher elevation (better solar incidence angle) when the sun comes around to the panel in the morning. 2. The thickness of the atmosphere should also bear on the amount of incident light that gets to the panels. Now these panels will have a peak wavelength of absorption, but there will also be a bandpass and most semi-conductors do better at the red end of the spectrum and even into the near-IR. The atmosphere has better transmission near the red end as well witness our sunsets. So, if the panels are not facing due south, then when the sun's azimuth is the same as the panel it will be somewhat lower in the sky and the sunlight will thus have to travel through more air. For visual light the thickness of the atmosphere at an altitude of 30 deg (zenithal angle of 60 deg) is twice as thick as at the zenith, perhaps slightly more as the secant approximation for air mass begins to fail at this point. I think we should be accounting for this in our models if the transmission of panel relevant wavelengths is appreciably attenuated. Again, if the panels peak receptivity is perhaps 710 nm then the attenuation due to air mass may well be considerably less. However, this should be considered until proven irrelevant. In the winter with the roof pitch, we might have an incidence that near 45 degrees, but the sun is not as bright due to the significantly thicker atmosphere through which it is shing due to its low altitude. 3. As an Englishman it is odd that you do not consider the effects of weather and cloud. In my location we are fortunate when the climate records give us more than a 40% chance of sun on any given day. So, the amount of generation and thus the financial return are going to non-trivially compromised and this should be in your model, which right now is better suited to a sunbaked desert somewhere. 4. The angle of sunlight incidence on the panel, at a any given time of year, will vary as it does during the day. My example at the top has the array on a roof that non-tracking. So, with a roof slope of 26 deg and a latitude of 46 deg, the winter incidence (taken as an altitude) is 21+26 =47 deg and in the summer, we can achieve 90 deg at solar noon. These angles need also be included as seasonal values. You did so with your graph, but again, weather at least here is often for more overcast in the winter than in the summer making for sun pct's in the 20% range (i.e. one sunny day every 5). 5. We have some incentives from the Federal government (the province would rather, it seems, have us burn coal) which will pay up to $1000/kW for solar panels. (max of $5000). For me, then it is just the inverters and getting someone to install it. I can get a system as DIY on-line so this saves some money. Right now the base number for getting a system done is about $3/W which is $15000 for a 5kW array. Given the lower prices for electricity, there is no way it can be justified ... without a divorce 😪. However, I can get a 4kW array, inverters and rails on line for about $5000, adding the costs of installer and permits => $7500 and I would get back about $2500 from the government as these panels only cost about 60c/kW for a net amount of about $5000. If I save about $60/month then it might pay in 7 to 8 years. We can also get an interest free loan from the Feds as well. 6. We now have a four-tiered TOU rating policy and so for the night it is only 2.8c.kWh and at max around dinner time it is 28.6c/kWh. The good thing is that the provincial government requires that generated electricity be rated at the same TOU rating as when it was given to the grid. So, at least in the summer, we would be producing some power during the late afternoon early evening high rate period. 7. I am very reluctant to move forward as the money is really close and there are ALWAYS extra charges and other requirements that no matter how one sources these things, I feel I can't feel sure that I have it all tied down. Sorry for the long post, but I enjoy your work, Henri van Bemmel

@GaryDoesSolar

6 ай бұрын

Thanks Henri, for this comment. It's a busy week for me, but I'll try to have read when I get a quiet moment :-)

@henrivanbemmel

6 ай бұрын

@@GaryDoesSolar Thank you!

Great Video, is any chance you could make a video about BIPV products? like solar tiles/solar glass/solar siding. Many thanks

@GaryDoesSolar

10 ай бұрын

Thanks, and I'll add to me (ever-growing) list of future topics :-)

Great video. I think the overall long term trend of lower electricity prices will continue though.

@GaryDoesSolar

2 ай бұрын

Thanks. Yes, hopefully that'll be the case! Cleaner electricity too :-)

Thanks for these excellent contributions Gary. Similar to one of the other comments previously, would it be possible, even if you can advise here what adjustments are necessary to calculate the solar generation for other times of the year? Is it a case of reducing the max array output by a given percentage to reflect what the average daily output for that time of year? Thanks in advance.

@GaryDoesSolar

Жыл бұрын

Hi Karl, thanks for taking the time to comment - I really appreciate the feedback. Thank you also for the kind words. Yeah, when trying to model anything real-world, the more realistic you want it to be, the more exponentially complex that model becomes! So, I thought to myself, let's just have a single solar model to cover all seasons (even though we know that the sun's hours reduce drastically in the winter) and allow the user to turn down the percentage for different seasons, according the the monthly chart in the video for the user's location. That's probably good enough to get a reasonable approximation, I felt. That said, if you go to the download link mentioned in the video and the video description, you'll see that some viewers have improved on my original spreadsheet :-) Hope that information helps!

Loved your videos, taking the plunge into solar PV system myself, i had a question. I have two battery options, GivEnergy that has a 3.6KWH output and FOX ESS AIO that has a 5KWH output. Which one would you recommend?

@GaryDoesSolar

11 ай бұрын

Thanks, Deepanshu :-) Now, I intentionally don't advise people on solar, but I will say that I went for a GivEnergy solution myself...

Hi Gary. many thanks for your videos which are very clear and have aided in building my understanding of solar / battery solutions; I feel better able to assess alternatives. One aspect I'm left confused about is charging and discharging losses, these form important assumptions in your spreadsheet. Taking a couple of examples the GivEnergy battery is DC, looking at the inverter specs I read 6% losses in both the charging and discharging process? Tesla Powerwall is AC coupled with 10% round trip efficiency which I read to be charging losses? These numbers are significantly different to the assumptions you suggest in the spreadsheet. What have I got wrong? Thank you

@GaryDoesSolar

Жыл бұрын

Hi Adrian, great to hear that my videos are helping you - thanks! :-) Now, on the charge/discharge losses in the spreadsheet, looking at the Tesla Powerwall first, round trip losses of 10% would equate to around 3% loss each AC-DC-AC conversion (remember the PW is AC-coupled, so 3 conversions). Do you have a link for the GivEnergy losses? I can't seem to find anything on the web... thanks.

Hi Gary, A couple of very informative and helpful videos, thank you. I've been having a close look at the spreadsheet and have a question and a suggestion; Question - On the "Solar with Battery" worksheet why is there an import cost in cell(M4) "0 Hour of Day"? (I would've thought the battery would've covered this) Suggestion - is born out of my own need to try and calculate the pay-back period. Therefore I have added a "Cost without Solar" column which I then total and use this total to calculate "Daily Savings" and "Annual Savings". This then gives me some idea of when I recoup my installation costs.

@GaryDoesSolar

Жыл бұрын

Hi John, thanks for the kind words. Now, the whole M column in the “Solar with Battery” sheet is only there so you can input the price/kWh (actually, that’s a better name for the column than “Cost/kWh”). Whatever you enter in cell M1 is automatically replicated into the rest of the column. Or, if you’re on a variable pricing throughout the day kind of tariff, you can just hard-code values throughout that same column. Does that make sense? Btw, I really like your idea of adding a new “Cost without solar” column 👍🏻 😀

@johnwalsh4899

Жыл бұрын

@@GaryDoesSolar Thanks for the prompt reply. Sorry I didn't make it clear, the M4 cell I was referring to was on the "Solar with Battery" worksheet and is the "Grid Import(kWh)" column. I don't understand why on the "Hour 0" row there is anything being imported from the grid. I would've thought the battery would have covered this period.

@GaryDoesSolar

Жыл бұрын

Ah ok - I get it now. I think you're referring to the cell L4, not M4, yeah? Basically, there is indeed a problem, but only because I was trying to be clever about the battery charging and level... I'll explain: Rather than managing the battery level from hour 0 until hour 23, I recognised that in real-life there would be charge in the battery at hour 23 that could be used the next day (hour 0 and so on) so I essentially loop from hour 23 back to zero. But in order to void the circular reference, I intentionally zero-out the battery charge at hour 6 - just before the sun comes up (the value of cell K10 is deliberately set to 0. The side effect is that if there was still charge in the battery at hour 5, this just gets lost. But it is just a spreadsheet and of course it will have limitations. So, to your point, if you change the formula in cell J4 from: =-MIN(MAX(F4-H4,0),0,$C$13) to: =-MIN(MAX(F4-H4,0),K27,$C$13) It should solve the problem. Can you let me know if it does, and I'll upload a new version of the document. Many thanks :-)

Hi Gary, great explanation and model. Do you have a version of the spreadsheet which includes battery storage as well as using the Octopus flux tarfiff (flux/day/peak tariffs) - I want to model charging the battery sufficiently during flux cheap period to allow maximum export during peak period while retaining sufficient battery capacity for the remainder of dark hours, and see what this does to the business case for solar byoptomising use of the Octopus flux tariff

@GaryDoesSolar

Жыл бұрын

Hi Gary, I most certainly do! And I have a video to go with it: www.garydoessolar.com/utilities/fluxcalculator/index.html You may prefer to use the web app instead of the video, which is also available on that link. Enjoy!

Very useful series of videos thus far - just what I need at this point of the solar panel installation journey, so many thanks Gary. Question on using the spreadsheet: Do the solar model or generation numbers (kWh) need to be adjusted for location (in UK) and orientation of panels or do you recommend simply using as is?

@youxkio

Жыл бұрын

I don't know if I can help here, but here is the website Gary mentioned about getting the numbers for the orientation of the panels based on location: re.jrc.ec.europa.eu/pvg_tools/en/ And, the calculator sheet: www.garydoessolar.com/utilities/solarcalculator/index.html

@GaryDoesSolar

Жыл бұрын

Thanks Ian - very happy to have helped you out! 😀 On the solar model, this is fixed for a south facing roof in central England, and other orientations would simply skew that model slightly (but not much). The EU link can provide you with the exact solar model for any location and orientation but it’s not the easiest utility to use.

@rjmacf0015

Жыл бұрын

Yes. See link from last video. Measure roof truss angle using your phone. Enter into re.jrc.ec.europa.eu/pvg_tools/en/

@thrillseeker75

Жыл бұрын

@@GaryDoesSolar I downloaded the solar model for my location but not sure which value to use in the CVS sheet. time,G(i),H_sun,T2m,WS10m,Int?

@GaryDoesSolar

Жыл бұрын

​@@thrillseeker75 The solar model in the spreadsheet is very simple in fact - looking down the column, you'll see that it is 0 for when there is no sun, and 1 when the sun is at its highest, with values in between forming a bell curve. Take the solar model you downloaded and try to fit it into that normalised range across the 24-period.

Thanks Gary - exceptional production. Really useful, as I have just had my system installed and wanted to understand the quirks of electricity production with respect to the available sunlight during winter of 22/23. The spreadsheet is fantastic and thanks for recommending Loop. Both are invaluable. I do have a question: if my solar panels are rated to deliver 5.7kwh then even on the sunniest days in winter, the maximum production is only 3.2kwh. Does this sound right or is there a problem with the installation/configuration?

@GaryDoesSolar

Жыл бұрын

Thank you for the great feedback - I'm humbled. And I'm so happy to hear the spreadsheet has been of use to you :-) Now, in relation to your question, are you saying that your array was rated (my someone) to deliver 5.7kWh on a typical winter's day? Or was that figure quoted for a summer's day? Winters are typically 10-20% of the summer generation, but it depends where you live. In any case, if your production is only looking to be half that, then it does suggest a potential issue. What I'd do in your situation is have a chat with those living nearly you with solar installations, to get a view on the percentage generation on a typical day (e.g. 4kWh on a 6kWp array - note 'h' and 'p') and see if that matches with your own generation. I would also write a post on a solar forum that you might be a member of. Provide details of your setup and also a couple of examples of the generation you're getting (ideally graph format). Then see what responses you get. Good luck!

@hungarianzozo

Жыл бұрын

@@GaryDoesSolar Thanks for the response. I will follow your suggestions.

Thank you Gary for a very informative video - I have been thinking about solar for a while but this just pushed me to make my decision to go for it - I was wondering if you had any recommendations on some good solar installers in UK please?

@GaryDoesSolar

7 ай бұрын

You’re very welcome, thanks for letting me know. The only installer recommendation I can make is EcoBubl - they did a fantastic job with my own installation earlier this year 😀 They’re based near Basingstoke and I have a video about that on my Patreon. Good luck with your solar journey!

Thanks for the great video! Could you explain why it is good/okay to have a maximum inverter output that is smaller than the maximum array output? That means you are clipping in the hours with most sun, so not using all the potential of your panels…

@GaryDoesSolar

8 ай бұрын

Hi Maxim, you're most welcome about the video - and hopefully you'll like some of my other videos too :-) Now "array-oversizing" as it is termed, has many benefits. This article from SolarEdge is worth reading as it explains them in detail: www.solaredge.com/uk/solaredge-blog/oversizing

@jock I have watched many of your videos Gary and subscribed. This one is particularly fascinating. I am convinced of the benefits of solar and would love to install a system but I live in the SW of France and the reviews of the larger companies here make such frightening reading that I am greatly discouraged. I don't suppose there is a way to reliably assess or evaluate an installer, or has one just has to take a leap in the dark.

@GaryDoesSolar

2 ай бұрын

Thanks John! Yeah, trying to find a reputable installer and good quality, reliable equipment is not straight-forward. I would suggest you look around your neighbourhood and chat with those who already have installations to see what their experience has been like - and whether they would recommend their installer... Good luck! :-)

Theres another reason to install solar panels and a battery wall...that is to keep the "LIGHTS ON" when the grid goes down and it will be happening more often in the future as we see more renewables coming in to service...add to that a EV and a wood fire with a "WET BACK" and a hot plat to cook on , you've got all the bases covered !!!.🤔💕🇬🇧

@GaryDoesSolar

Жыл бұрын

Totally agree!

@robertsprigge5535

Жыл бұрын

Solar panels installed, but the LuxPower battery system has been delayed. It's set up to benefit from Octopus flexibility, with extra Octopus friendly functions on request. I was surprised to learn that UK DNOs severely limit what you can do when there are power-cuts😞I'll be going for continuous battery output rather than power-cut only supply. The installer is only offering four sockets in a block and I'm having difficulty deciding where they should be installed for the best outcome.

Great video and thanks for the spreadsheet. But where do you get the ‘Solar model’ figures from?

@GaryDoesSolar

Жыл бұрын

Good question! In fact for the spreadsheet I just used a Solar profile for a south facing roof in central England. This could of course be improved upon… 👍🏻

@stevesmith7675

Жыл бұрын

Very informative Gary. Thanks for taking the time and trouble to do this. Is there a link to a website showing hourly sunshine levels?

@ipb1966

Жыл бұрын

@@GaryDoesSolar Thanks. Probably the best video I’ve seen on payback calculation and makes my spreadsheet look very…amateur! But it is difficult - we’re on Octopus Go Faster with five hours reduced rate 20.30-1.30. But there are a lot of “what ifs” - if we move this to this time…etc. Personally I think a battery is essential. Yes you can move the dishwashing etc to during the day but if a cloud goes over you start pulling from the grid which potentially could make it more expensive than using it at off peak hours. And I think for people who can’t have solar for whatever reason but can get on Go, a large capacity battery might be a good idea, that way you know you will never pay more than the off peak rate, as long as the tariff exists and you’re careful about simultaneous appliance usage.

@GaryDoesSolar

Жыл бұрын

Steve, I haven't ever seen such a site, but would love to! The best alternative is the scientific EU site: re.jrc.ec.europa.eu/pvg_tools/en/ - they have massive databases that cover the planet but I'm not sure how you would extract the information you're looking for.

@GaryDoesSolar

Жыл бұрын

@@ipb1966 Thanks for the kinds words. Yes, there are pitfalls with just a solar solution as the sun is not guaranteed throughout a sunny day. This is where a battery comes into its own :-)

Hey Gary, echo the sentiments of the other comments, great video as always, I'm learning so much from watching your videos. I just wondered where the Solar model comes from and does that need to be adjusted, I watch your other video featuring the PVGIS tool, but I can't see how you've translated the data it provides for use on the spreadsheet here.

@GaryDoesSolar

9 ай бұрын

Hi Rob, so the solar model in the free utility is a very basic bell curve that I coded up - it's a normalised profile for a South facing property in the UK. It's likely good enough for those who want to get a rough idea on how their planned system might perform during the day, but for those who want a more detailed view, then the Pro Edition of the tool is a far better option. I've been developing that a lot lately, and there are now two solar models: - An improved simulated model that takes into account the geographical location and orientations of up to there arrays - and also the number of sun hours in summer and winter - Data from the EU PVGIS system (re.jrc.ec.europa.eu/pvg_tools/en/)

Thank you Gary for the very informative video. I tried to download the spreadsheet however your website seems to be down.

@GaryDoesSolar

Жыл бұрын

Thanks for the kind words 👍🏻😀 Now, can you try the link please? I just tried here and it seems ok

@berilevi3177

Жыл бұрын

@@GaryDoesSolar it’s probably my work network blocking it. I will try again later in the evening from home.

@GaryDoesSolar

Жыл бұрын

Did you get any joy, Beri?

@berilevi3177

Жыл бұрын

@@GaryDoesSolar Yes, I could download it from home. Cheers, Gary.

Very useful. There appears to be an error in the spread sheet for solar with battery on hour 6. The battery level is set to 0, rather than the previous value + discharge.

@GaryDoesSolar

Жыл бұрын

Thanks Roy - that's now been corrected in the latest version of the spreadsheet - just click on "Check for new versions" to get it. Basically, I forgot to loop the battery level at the end of the day back to the start of the day. Thanks for spotting the error! :-)

HI great Video and Spread sheet . Two questions: in the spreadsheet you use solar model data . Where did it come form and which month of the year is it or average. As Would like to model for each month of the year. Second on the battery sheet the price calci=ulated does not seem right as it seem it the cost are only based on the charging at night and regardless of the size of the battery it does not seem to charge for electri after it has depleted the battery! Hope you understand the above Simon

@GaryDoesSolar

Жыл бұрын

Hi Simon, thanks for the kind words. To answer your questions: 1. The solar model was taken from a sample of a south facing array near Oxford in the UK during summer. If modelling for other months of the year, it will be the same bell curve shape, but the sunrise and sunset times will be closer together. 2. Yes, the "Just Battery" sheet is purely battery and no solar, to allow you to see the effect of time of use rates. There is the opportunity for someone to combine it all into one sheet, but I didn't have time.

Hi Gary, I am using your v1.01 spreadsheet and I am unsure if you have errors on K10 to K14 cells on your solar with battery tab. Using my consumption figures I have a battery level that goes from 12.10 (K9) to 0.00 on K10 for a consumption of 0.092 kWh value. this then shows a battery level of 0.74 (K11), 3.05 (K12), 6.05 (K13), 9.05 (K14) before then going back to 12.05 (K15). These are between 6am and 10am. My max consumption between these times is at 7am with 0.361 kWh consumption. I would just like to say that all 3 of your videos have been incredibly helpful and informative as we are getting quotes to have a panel and battery installation installed.

@GaryDoesSolar

Жыл бұрын

Hi Adrian, really happy to hear the videos have been useful to you, thanks! Now, for the battery Level column (K) there is a little trick I had to employ. In order to allow residual charge in the battery at hour 11 to be used overnight, I had to wrap around the formula in that column. This creates a 'circular reference' issue, so to avoid that I had to zero out any remaining charge at hour 6 (see cell K10) which is the hour before the sun comes up. I couldn't think of any other way to solve it, and I guess this is one of the limitations of trying to use a spreadsheet to model the real world! Does that explain why you're seeing what you are, or do you think there are other issues in the spreadsheet?

@adrianlynch9435

Жыл бұрын

@@GaryDoesSolar Hi Gary, sorry for the time gap between my responding - I though KZread would alert me to a response, but it didn't. I have tried multiple methods to try and remove the circular referencing and I can't. I did find a way though and that is if you make a cell below the table calculate that value (using your existing formula) tied to the cells that you would need and manually type that value in (or paste as text) then the table works as it should do. The circulatory reference is broken as that is just a number and not a formula. I was also thinking about the difference in production over the year and I wondered if instead of recalc'ing everything you could just drop the size of the array (kWh) to a lower value and therefore in effect generate less but in proportion to the time of year ?

@GaryDoesSolar

Жыл бұрын

No problem on the delay, Adrian. Yeah, I seem to miss notifications too. Circular references on spreadsheets do my head in! Lol Yeah, that's the only way I could find to break it - making cell K10 just '0'.And yeah, dropping the array size is the way I think works easiest (and the reason why I named it "Max array output" rather than "Array size") - next step for me will be to build an actual online utility... 🙂

@adrianlynch9435

Жыл бұрын

@@GaryDoesSolar I think I have fixed the circ reff'ing issue Gary. I can't post the web address as KZread keeps removing the comment no matter what I try to do with the web address. Anyway, in excel go --- File, Options (very bottom left) "Formulas" selection -> and on the right hand side is a tick box labelled "Enable iterative calculation" (I left the two maximums as default values) and select OK. I then copy n pasted the folmula from the cell below and it works fine with no circ reff'ing error. If you do this again and untick the box the circ reff'ing error returns.

@GaryDoesSolar

Жыл бұрын

Thanks Adrian - I'm learning new stuff from you about Excel 🙂

Thanks for the video. Is it possible to add dual tariff charging to the solar + battery spreadsheet please? My solar isn't enough to fully charge the battery so I will be topping up during the off-peak hours.

@GaryDoesSolar

Жыл бұрын

Hi Paul, my pleasure. Now, I did think about just that but thought it might be getting too complicated for one video. If I get time, I'll add an additional tab sheet into the file.

@Alcatraz2k

Жыл бұрын

@@GaryDoesSolar that would be great thanks