Good idea for storing excess heat, but without Soviet style communal heat pipe networks it’s basically useless because the transmission loss of distribution is already applied. And if you’re using solar panels you’d have better luck just putting the pots in the sun and bringing them in later.

What Is a Sand Battery? Polar Night Energy’s Sand-based Thermal Energy Storage Explained - YouTube

Polar Night Energy’s sand battery is a large-scale high temperature thermal energy storage that uses sand or sand-like materials as its storage medium. It stores energy in sand as heat. It has three main purposes: To store excess wind and solar energy, to participate in grid balancing markets, and to produce heat and power without burning. The sand battery has a lot of potential to save emissions. Cleaner energy production is possible. Together, we can power the change from fossil fuels to renewable energy.

I really liked the video but one thing irked and annoyed me.

1:34 “A product to convert heat into electricity is being developed.”

And they don’t explain that at all!

All electric heating is essentially the same: watts in > heat out.

There’s a small degree of variation depending on what you choose but don’t be convinced that there’s truly better or worse options overall.

With that being said, here’s some tips for heating:

• Oil heaters and panel heaters are good for maintaining a stable temperature over a long period because of how they work - this is good for places that get below freezing during winter. For anything else, they aren’t ideal because you’re better off heating your space when you’re in it and switching the heating off when you leave.

• Radiant heaters can be more effective overall but they come with some risks

The risks are to pets, the elderly and the infirm. They can also start fires if you aren’t careful when using them.

Don’t use them in spaces where there’s risk of something like a towel, a blanket, or curtains coming near them or falling on them - that can start a fire.

Radiant heaters lose a bit of efficiency because they also put out light but it’s fairly minimal and it depends on the type of radiant heater you use.

Where they shine is in how they immediately heat whatever they point at - this is instead of heating up the air and then that air heating you up. This makes them ideal for places where there is a lot of air space or a draughty house. They’re also good in bathrooms because you can heat yourself up without losing a lot of energy to air circulating because of a ceiling fan.

• Direct heating is the best

Yes, there’s the watts in > heat out equation that is largely the same. The difference with direct heating is that you’re only heating the space that is right next to your skin rather than trying to heat a whole room or house.

Electric blankets and throws as well as heated vests, heated foot warmers, and hot water bottles are all examples of direct heating. Where it’s safe to do so (check your instruction manual) you can heat beneath a layer of insulation like a winter jacket or a thick quilt. This means that you will get a lot of the direct benefit of the heating and you will trap a lot of what would otherwise escape, making it even more efficient.

As a general rule I think it’s safe to assume direct heating is worth about 10x that of what you’d get from indirect heaters; if a typical heater works at around 2000w on high and 1000w on low, then 200w from a direct heating source is roughly comparable to what you’d get from a typical heater on high. This depends on different factors though.

One downside of direct heating is that it doesn’t heat the air which can be a problem for people who are sensitive to cold air, such as asthmatics.

You can definitely set up an arrangement where you have a space heater to take the chill off the air at the lowest tolerable air temperature then use direct heating to make yourself warm and you’ll still save a lot of money.

I haven’t discussed the role of heat pumps because that’s a very complicated matter and it depends on the real-world conditions that it’s operating under - when it was last cleaned, what the ambient temperature is, whether it’s ducted or it’s in a single room (hopefully the one you’re spending your time in!) and considerations like the cost comparison between gas heating and electricity prices.

As a general rule, heat pumps are more efficient and without sitting down doing a lot of maths I’d hazard a guess that it’s your best option, if you happen to have it.

Also don’t take this guy’s videos too seriously with regards to DIY evaporative cooling seriously - in theory they are useful but in a practical sense they generally aren’t and depending on the conditions they are operating under they can actually be counterproductive. I can elaborate on this if anyone is interested but basically I wouldn’t waste my time or money on making a DIY evaporative cooler (nor would I buy one of those little personal evaporative coolers).

I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy:

• yewtu.be
• inv.nadeko.net
• yt.artemislena.eu
• piped.video