We have just started to gather some evidence on how people cook. It might seem amazing given the huge amount of work on Improved (Charcoal and wood) Cookstoves, but other than Cowan 2008, we have been unable to find details on how much energy it actually takes to cook a meal in real world situations. Of course there is data on how much charcoal people consume, but cooking with charcoal is not the same as cooking with modern energy. It is that much easier to simmer food by turning down the gas or the electricity. [Indeed the picture is of wasted energy!! – why have the gas so high on such a small pot, the heat goes up around the pot! (and why doesnt it have a lid?)]
True, there is evidence that households manage their biomass fires to minimize use of fuel. One of the founders of Gamos was Prof P D Dunn. He is author of books and started the first Masters course on Renewable energy. Indeed he started the engineering department at Reading University. Sadly, now deceased. Anyway, even in the eighties he told stories of his work in Thailand on improved stoves, how they were lab testing stoves. One day he came in out of hours and found the cleaner cooking on one of the stoves. She was pushing sticks in and out, and as he watched he realized she consumed about half the wood that the lab technicians (men!) did when they tested the stoves. So it has been well known that real world cooking is not the same as lab testing.
But beyond that, modern energy whether gas or electricity does give a greater control to the cooking process. Instant startup – rather than using charcoal in the startup process. Instant turn off. Ability to reduce power to simmer. These all effect the total consumption of energy.
So as we attempt to build optimum ecook systems, we need to know – how much energy needs to be stored in the battery to give households enough to cook their meals?
All sorts of unknowns. Are they cooking raw materials from scratch? Reheating a left over meal for breakfast wouldn’t take anywhere near as much as a raw material. When cooking Ugali, it is very important to stir all the time – but is that because you don’t want the bottom to burn. How much storring is needed if you turn down the heat.
Anyway – interesting questions which we are trying to answer. We have developed a protocol that involves getting (urban) households to sign up/commit Some are charcoal, some are LPG users. They will keep a detailed cooking diary for two weeks – what they cook, and how they cooked it. And the enumerator will measure the fuel consumption. Then we intend to give them an electric stove (just a single or double hotplate). They will cook for 4 to 6 weeks and we will measure the energy consumption and they will keep their cooking diaries.
We had debates over whether to advise them on how to cook with electricity, and how to save energy, but I think we are just going to leave them to it and see how that transition from charcoal to electricity works out. Plenty of time for more nuanced studies building on our first findings here.
(If anyone knows of studies looking at how people (in LA, Asia or Africa) cook on gas or electricity, please let me know.)