[jodrellblank]

> so about 0.5kwh

It takes 1.16 Watt-hours to raise a litre of water by a degree. Say 85Wh for 15C room temp to 100C boiling. Assuming your large meal for three is 3 litres, that's 255Wh to get the water boiling. There's energy loss from battery through inverter, through induction. Loss in the pot losing heat to the air. This doesn't count keeping it simmering, or heating the other ingredients.

I don't have any idea if that's very good, to be only twice the theoretical minumum, or quite a room for improvement - have you ever experimented with a 'pot cosy' to insulate the pot and stop radiated heat loss so you can keep it simmering with less power input, or turning the heat off once it's boiling to let pasta or rice cook in the residual heat, or anything?

[ethbr1]

> 'pot cosy' to insulate the pot and stop radiated heat loss

Is this a product that exists?

The closest I could find was ceramic fiber insulation [0], which could presumably be cut to shape and fastened (high temp fastener?) into pot shape.

[0] https://www.amazon.com/s?k=ceramic+fiber+insulation

[jodrellblank]

Yessss, more or less. I learned of the idea from this guy's content[1] who bikepacks ultralight and wants to save camping stove fuel, and he made his own. And from my dad who habitually wraps a thick teatowel around stew pots, on principle (he doesn't measure for a difference in power use. Electric cooktops only, not flame ones). Since it has to be snug on the pot, making one is probably the common way forward.

A few products do exist in that ultralight camping world, the Toaks D95 Pot Pocket[2], the Trangia Pot Cozy[3], Glacier Minimalist "pot with insulating sleeves". In standard size maybe the "So-Vida Sous Vide Insulation Band and Mat for Pots - Protects Your Work Surfaces and Saves You Electricity From Increased Insulation"[5] which is out of stock.

The Wonderbag[6] marketed as for communities in Africa and not available in the USA. From the Wikipedia page on Thermal Cooking[7], in a normal size kitchen people probably go with a vacuum flask cooker, popular in Asia.

[1] https://www.tristanridley.com/post/2019/01/21/diy-pot-cosy-t...

[2] https://www.toaksoutdoor.com/products/coz-m

[3] https://trangia.se/en/shop/pot-cozy/

[4] https://gsioutdoors.com/products/glacier-minimalist

[5] https://www.amazon.com/stores/SO-VIDA/page/BB00BAE8-07C8-4B4...

[6] https://en.wikipedia.org/wiki/Wonderbag

[7] https://en.wikipedia.org/wiki/Thermal_cooking

[testing22321]

No, I never tried.

I have a 200Ah lithium battery, 600W of solar and a dc-dc charger.

To be honest, using up 20% of my battery to cook a large dinner is not a big deal or something I need to improve.