Temperature is no indication of energy produced. A soldering iron tip can easily produce more than 350 degrees C with a consumption of 25 W. If you put it in a pot of sand it will probably give you similar readings but it will hardly do any good heating a room in the winter. What the sand does is to store the energy and radiate it in a slower rate in the environment. I am afraid that either with or without sand with a supply of 100W from the power supply, 100Wh will be produced which is what would be given by any other 100W heating device.

@mikeshawbrook-selfreliance

6 ай бұрын

My interest is in warmth. Due to the heat retention properties of sand the energy put into it dissipates at a very slow rate and as such builds up cumulative energy. In other words, the energy input is an average of approx 65 Watts per hour. But it takes the sand way longer to release that energy. As a result the sand get scorching hot. And with the fan I can enjoy the heat from that. Had I just used that energy to light a lightbulb, I would not have the same conditions

@jaredcarlson3500

6 ай бұрын

​@@mikeshawbrook-selfrelianceyes, but energy in can only equal energy back out. It's just a heat battery. If your adding the energy slowly at a low rate, more time is required to charge the heat battery. If you heat it at 50 watts for 10 hours, you've charged it with 500 watts of heat. If I heat it at 500 watts for 1 hour, I've accomplished the same goal quicker, but used the same energy. There isnt an advantage.

@mikeshawbrook-selfreliance

6 ай бұрын

@@jaredcarlson3500 Energy in = energy out, I am aware. It is more aimed at using solar energy that I stored in a 600W battery unit. I can run my "installation" approx 9 hours on one charge. As the sand has a high heat retention ratio it will "accept" the 600watts and give it back over a period of 9hours+ at 70watts, rather than one hour at 600 watts.

@jaredcarlson3500

6 ай бұрын

@@mikeshawbrook-selfreliance ​aha! Then you have succeeded. Thank you for sharing your work with sand batteries. I love how simple and robust they can be!

@carlhoward5469

6 ай бұрын

This is kind of all nonsense. *All* electric heaters are 100% efficient. It all depends on how fast you're gaining energy (heat) compared to how fast you're losing heat, and that's almost entirely dependent on how well you're insulated from the external environment. If I have a well insulated container, I can get it up to extreme temperatures with any little heating element. But then the higher the temperature differential the faster you lose heat due to thermal diffusion and black body radiation. Not rocket science ...just high-school level physics. 😁 Edit: I agree with your post entirely... I'm just commenting about the video in general. 🙂

Love the idea. Great work. What are the elements called. How would i aquire some?

I would put a pipe through it and bring it in a "U" back up to the top where your fan is. Then insulate the heck out of it so that the only heat loss you will have is where it is being blown out through the pipe. It's not gonna move a lot of air but it could be run from a car battery, so that makes it nice for a small area. Of course your wattage is gonna go up the better you move the air through the pipe. What do you think?

@mikeshawbrook-selfreliance

6 ай бұрын

Wonderful idea. I need to try that

Hey Robert, they are called PRC elements. I put a link in the description of the video

Improvements are relatively easy to make , but there is a question of regulation of heat exchange. Besides insulation , which has to be substantial , because of very high temperatures that sand battery can achieve , the best way (depending on the volume of the container filled with sand) is to heat it from below (close to the bottom of sand container). That creates problems with insulation of the connecting wires , unless the heating elements are inserted into container trough the bottom of it (with wires outside of container). Many people had that problem (with insulation on the wires , inserted from the top) , which is not a problem , if you make necessary changes to the container (metal bucket with a metal lid can be used , in order to drill , or cut the holes in the bottom , for the heating elements). The only way to regulate exhaust temperature (air to air) , is to limit the maximum temperature within sand battery , via high temperature thermostat , which will cut power supply to the elements (at given temperature). That limits full potential of the sand battery , but there is no inexpensive way to do it otherwise , when it comes to home use. For insulation , ceramic wool should be used (stuff for insulating the kilns ) , because ordinary rock wool works only to about 200 °C , after which it melts. Ideally first layer of insulation should be carbon felt (pure carbon felt , like welders blanket). The heat ex-changer can be metal pipe or strip , with fan blowing over (or trough) it , depending on a temperature of sand , because this thing can absorb well over 1000 °C. Good luck with the project !

@mikeshawbrook-selfreliance

7 ай бұрын

Thanks for the feedback :-) It's highly appreciated

Heat is one measurement... one would need to evaluate the BTUs to assess the usability of the device... or at least try it to see if it can maintain a reasonable temperature in a room with no other heat source.

@pedjamilosavljevic6235

7 ай бұрын

There is whole lot of measurements that could be applied , however , this is a well known "device" , or principle . Sand batteries DO work very efficiently and can reach extremely high temperatures (over thousand degrees C). Insulation of the battery and heat exchange are different topics. Room doesn't equate to anything , because there are big rooms and small rooms , well insulated and poorly insulated , etc... In this case , man used about 75-77 W average for 30 mins (which equates to cca 150 WH) to heat (at least top of the sand) to 110 °C. Every heating unit has efficiency of abut 98-99% , so only benefit (in this case) is utilization of ceramic heating units , which are more durable , than standard stainless pipe heating units , which wear out more (resistive wire inside them has certain amount of cycles , before breaks ).

@mikeshawbrook-selfreliance

7 ай бұрын

I did experiments like this before and receiced many questions about the room. The starting temperature and whether it could heat it. I believe this would not add a lot as there are too many variables such as humidity of the room, altitude of the building compared to sea level, size of the room, insulation etc. Thanks for the feedback

I don't understand what is interesting or new new in this video. You have some resistive elements in sand and they produce heat when you apply power. Totally expected. And the temperature also isn't astonishing. Just take a look at a simple old incandescent light bulb. There the temperature is much higher with similar power consumption. But I have subscribed nevertheless - maybe there's an aspect to it I didn't get yet...

@mikeshawbrook-selfreliance

6 ай бұрын

First of all, thank you for subscribing. The intention is to store the energy in the "sand battery" so the energy put into it can be released slowly over time. If I turn off the power at 11pm the fan is still running at 9 in the morning. I know it does not miraculously make energy out of thin air.

My good friend, I'm telling you this with love, you have a really bad understanding of physics and the difference between temperature and thermal energy.

@mikeshawbrook-selfreliance

6 ай бұрын

Noted. I am open to educate myself

@Sekir80

6 ай бұрын

@@mikeshawbrook-selfreliance Hey, I'm new here, could you explain your goal with this project? Just in a couple of words.

@mikeshawbrook-selfreliance

6 ай бұрын

@@Sekir80 I charged my battery pack with solar up to 600Watt. This will allow me to run my "installation" for about 9 hours with "free" heat indoors

@Sekir80

6 ай бұрын

@@mikeshawbrook-selfreliance Thanks. For clarification: your "battery pack" is the sand battery? 600 Watts is a measure of power, not energy. Did you mean you injected 600 Wh energy into it? Your "installation"? I don't quite get it. What I suspect: You have created a heat battery to store the heat generated by electricity (from solar panels) and it takes about 9 hours to cool it down, indoors. How am I doing with guessing?

@mikeshawbrook-selfreliance

6 ай бұрын

Correct@@Sekir80