Sounds great!

This is a dirt cheap way to store a lot of energy, for all 24/7 use. For space heating, water heating, for steam production if you have a steam electric power plant.

In cold areas the vast majority of our energy usage is used directly for heating. So if you could store a tremendous amount of heat in a mass of sand and use it somehow, i.e. flowing water or air through the mass. You have a very efficient way of storing heat. People often think of electricity storage when they hear the word "battery". But this is specifically to store thermal energy, and if used properly can be very efficient.

I just pulled out a bunch of the wire, and connected the positive of the solar panel to one end; with the solar panel in full sun. I connected one lead of the amp meter to the negative of the solar panel, the other lead of the amp meter I moved along the resistance wire until I got the rated amp load stated on the solar panel, and cut the wire there. -Trial and error.

@@doubleMinnovations love it perfect solution without acalculator

Using photovoltaics may not be an efficient way to generate heat, but it sure does simplify a lot of things. With the low price of PV these days, it's totally worth it. I use PV for all my hot water so there's no plumbing/pumping/leaking/possible heat exchangers, etc. involved. Very low maintenance, no moving parts, and the location of the collector isn't tied to where the energy is stored.

@@fxm5715 I do completely agree with the simplicity point. But you must not use hot water much, or have a different idea of "low price". Average hot water power consumption in the US is 10-15 kWh/day. Unless you buy in substantial quantity, PV price is sitting in the $1/watt neighborhood. Keeping in mind that in most of the US there is an average of 4 hours of full irradiance per day, 10 kWh / 4 hours = 2.5 kW/hr, or $2500 worth of solar panels if that's all your hot water. A space blanket costs around $1 for (more than) the same area of sun capture as a $100 PV panel, while being somewhere around 3-4ish times as efficient. We're talking about $5-$10 worth of space blankets to compete against your $2500. Even if you got a great bulk deal by buying a large 5-figure system plus government subsidies so it only cost you $1000 for the panels we're talking about here just for your water, I'd still consider the fact that for the $1000 spent on panels just to not have water flowing through a little extra pipe it could have been generating enough power for multiple entire households, and enough if you so chose to focus it right, to melt metal and turn sand into glass. The pipe, btw, probably costs around the same as the extra cable you had to run to get 2.5 kW from your panels to your water. If you didn't notice, I've been rounding everything against myself here. I'm not saying PV is overall a bad thing. If it's what you use for all your power anyway, by all means find every way you can to make use of it. But I still find it difficult to watch someone making heat with a solar panel's output without thinking about how you could get the same amount of heat production in less space and time for 1% of the cost, with only some aluminized plastic instead of an exotic sandwich of semiconductors and current collectors. Anyway, the whole point of a sand battery is that it's cheap. It's nowhere near as convenient or compact, but it drops the cost of storage to, well, dirt. Seems odd to pair that with the most expensive renewable which *already comes in as heat*. It'd make a lot more sense if the power source was wind or hydro or something. So ultimately I agree that PV panels are more convenient than space blankets. But I do not agree that they're "worth it" for the use case of heating. With regards to reliability, I think there are points on both sides.

@@user-hf3ym7lh4d Yes, I live alone, and only have to account for one shower and washing dishes on a daily basis. My total energy consumption is less than 14 kWh/day, and that includes high demand summer AC use. Laundry is washed cold. I've got only 600 watts of PV specifically dedicated to heating water, but that's more than enough to keep up with usage, on average. I can go three days without using up my hot water tank. The tank automatically switches to municipal current if the temperature at the top of the tank drops below a certain point. That usually only happens in the winter months when there's less light in general.

We have 1,920 watts of PV grid-tie. That more than takes care of our 'annual' electric hot water needs for 2 people. For 3 months in the winter the power output is pretty low. Be nice to think up of a durable, inexpensive, way to charge something up with high temp heat over the whole summer, and make use of it through the winter.

​@@doubleMinnovations That's a really tall order. A lot of power to store for a long duration. I feel your winter solar pain though, I'm up in Maine. The usual answer at home scale is batteries obviously, but not cheap unless you want to build them yourself. You'd have to get into the layers and rolls constructions I was talking about in the comments on those videos, though. Not just a single rod or pipe, you'll never get the density you need that way. Even then, most rechargeable chemistries don't do very well holding the same charge for months, even professionally designed and produced. They tend to either self-discharge or break down. The usual answer at utility scale is pumped hydro where they pump the water uphill to charge it and drain it back down through a turbine to discharge. It'd be a cool use for your past turbine work, but it's only cheap at huge scales, unless you happen to already have a giant pond on top of a more giant hill in an area that doesn't freeze much. You could try the same thing with logs or something tied to a rope connected to a winch, but the parts of your property seen in the videos are pretty flat, you'd still need a big (and steep) hill or extremely deep hole. And a ton of otherwise unused space. I did the math once on covering our entire roof with water capture, I think somewhere around 40 by 60 feet if I recall. Turns out the house would collapse before we stored enough to power everything for a single day. So we're talking pretty massive size and weight for months of energy. At *least* a large farm scale irrigation tower, and likely several of them. And they have to keep themselves heated enough to not freeze. The thermal battery thing is theoretically very cheap, and already being commercialized in Europe. But I think you'd need to do a very good job on the insulation of a very large battery. They do self-discharge obviously, so you'd need to scale up a lot. A smaller thermal battery self-discharges faster because of the surface area to volume ratio. As you scale up, the surface area scales as a square, but the volume scales as a cube. So a larger thermal battery can store more heat relative to the amount it dissipates through insulative losses. Again, the scale of what you're wanting to do just translates into equally massive solutions that raise more practical problems. I'm not sure that any of them will scale the way you're hoping for, but there are other unconventional options that make for fun experiments. Like fuel production. Use the excess power to gassify or pyrolize biomass or waste plastic or whatever into methanol or biogas or whatnot. I'll give a nod here to hydrogen, because you can't hardly have an energy conversation these days without it. I've heard of spare PV output being used to electrolyze hydrogen out of water, but I haven't heard of it being done at home scale. Storing it and using it safely requires some detailed knowledge. Without proper design and particularly material selection to avoid steel embrittlement and suppress static buildup, your hydrogen tank becomes a vehicle-sized fragmenting pipe bomb that can go off because of an invisibly small spark from a dusty breeze on a dry day, even if it's been working fine for months. Also, because an oxyhydrogen flamefront can exceed mach 30, it's rather difficult to burn in a controlled way without flashing back through the supply line and blowing the tank if you don't have absolutely *all* oxygen purged from the system. Hydrogen can be fun but make sure you know what you're doing before you scale that up. Burned all my forearm hair off playing with that stuff one 4th of July, and that was just a little partially inflated produce bag at atmospheric pressure. OTOH, circling back to where I started, you could drop a few dozen to a hundred or two dollars on Amazon for some space blankets (or maybe they have mylar in bulk rolls) and have usable amounts of thermal power even in the seasons when the sun isn't very high. This is one of those situations where generating more power is cheaper and easier than trying to store it, especially if we're talking about thermal. Then your problem collapses down to storing enough energy for a few stormy days at a time instead of months, so the thermal battery would probably totally work for cheap even without huge fancy vacuum insulated storage tank arrangements. I'm planning on testing my proposed setup, I'll let you know how it goes. We still have another foot of snow in the forecast, but this has been on my mind for a few years, and I finally have the space to try it out now. So some time this year. It'll either be "I told you so" or "I burned my heavily forested property down with space blankets." :) Tangentially, do you have any wind on that giant open flat property of yours? I was thinking about what a massive amount of wind energy you could capture for cheap with a large tarp or two fastened to a light frame on a rope between two trees for support, spinning on a vertical axis tied to the rope, or using the rope itself as a horizontal axis. Have an old broken winch I was going to use as the generator. It's another tree you could try barking up for ultra cheap power, orders of magnitude larger and cheaper than usual home wind turbines. It'd capture so much while being so light, that you'd have to design some flexibility into the structure just so it doesn't snap in a storm. Anyway, not sure if anybody is going to read all that, but I appreciate your videos. I find them a useful catalyst and reminder for my own ideas. Plus you're just about the only one out of my 3 digits of channel subscriptions who engages in the comments with any regularity. So, thank you for your time. I hope something I wrote here was useful enough to be worth the reading the small novel I apparently just wrote.

Use ORC for greater efficiency.

All the lengths of nitinol wire are connected to an off-set cam wheel. The lever you see me using, controls the position of the cam wheel, which directs when the tightening of the nitinol happens as it enters the hot water.

@@doubleMinnovations First of all, I thank you so much for responding sir! Second, can I send you a private message on a social platform? (Mail, Facebook, Discord, Instagram, etc)

I consider the comment section a social platform. Many people like to read and respond to other comments. If you have a question, you can ask in these sections, then all can see. But place them under the video it pertains to. There is an email address on the channels homepage, but I don't give out personal information.