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In terms of efficiently using sun's energy. Let's not forget passive solar. With no mechanical parts to break, a sufficiently heavy or phase change thermal mass can go a long way when the house is properly insulated. 4 m2 of windows (40 sq ft) is close toe 4 kW. (circa 12 000 BTU )


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There's an interesting summary of the situation in the UK here. In short, the most widespread option is likely to be heat pumps, despite some significant disadvantages, such as cost, and that fact that they don't always work well with existing heating infrastructure. It may be that hydrogen, generated by renewable power, will also play a significant role - ...


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Rice hulls , and I think other small grain hulls should be very good . Some pillows are stuffed with rice hulls ( the TV advertisements claim they are wonderful ).


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Until I see a lifecycle analysis of safety razor shaving vs. electric shaving to show electric is more sustainable (less water, less soap etc.), I would say safety razor wet-shaving seems to be the most sustainable and accessible, at least vs. plastic cartridge razors where you have to routinely throw away mixed metal+plastic pieces that will never be ...


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One of the things about substitutes is sometimes they don't match the real thing. I was first introduced to carob as an alternative to chocolate years ago. As nice as carob is, I still prefer chocolate. Likewise with coffee substitutes, they will only become widely used if people like them or prefer them to coffee. Coffee substitutes have been around for a ...


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My company Green City Living addressed this in 2014 when I invented the Bacon Sponge. It’s an absorbent towel that releases the grease when soaked in hot water and a degreaser soap like Mrs Meyer or Dawn for 15 minutes. Then it can be washed in the laundry with towels. It’s 100% cotton and biodegradable. https://greencityliving.earth/products/bacon-...


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A while ago I worked out that a $100/T carbon tax translates to about 6 c /liter (about 25c/gallon) This probably won't push people to drive much less or to buy smaller cars. However EV's are increasingly a better deal in terms of TCO, mostly because electricity is sold at low prices due to both subsidies and external costs. A tonne of coal is about 2460 ...


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Hmm. Going after your intent, I'm going to lump all fossil fuel into this, and include coal and natural gas too. I'm going to also assume that while the chemical engineers can turn almost any organic into any other organic for a price, we will consider that you really mean, "without breaking the bank" Asphalt. Used in huge quantities, and the ...


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