One example is bread. I was baking bread the other day, and obviously the cost of the ingredients I put in the loaf are less than the cost of buying a loaf at the supermarket, but that doesn’t include the cost of putting the oven on.
Or dry beans vs canned beans; does the cost of boiling the beans actually bring the cost up to be equivalent to canned beans?
I know that everyone’s energy costs are different so it’s not possible for someone to do the calculations for you, but I’ve never bothered to do them for my own case because bills I get from the energy company just tell me how much I owe them for the month, not “you put the oven on for 30 minutes on the 17th of June and that cost you X”. It sounds like a headache to try calculate how much I pay for energy per meal. But if someone else has done that calculation for themselves I’d be interested to read it and see how it works out. My intuition is that, in general, it’s cheaper to make things yourself (e.g. bread or beans like above), but I couldn’t say that for sure without calculating, which as I said seems like it would be a pain in the ass.
I don’t have a calculation to back it up, but I’m inclined to believe store bought will always have a cheaper production cost. Your can of beans wasn’t made by one person per one can of beans at a time. It is done in a factory producing millions of cans. That kind of industrial process will always be cheaper. It’s designed to be that way. Beans can be bought wholesale below the cost available to you. And with that operation at scale it will undoubtedly be more energy efficient per can of beans. The consumer cost is something else. You will save money buying the raw ingredients and making your own beans rather than buying canned.
I did the math a little bit ago because I was baking a lot of bread, and I think depending on the bread it was actually cheaper to buy the same kind of loaf baked in my grocery store than to buy the equivalent ingredients. This was a Publix though which at least in my area are on the more expensive end and they didn’t have store brand bread flour so I had to go with a fancy brand.
I think, but cannot be certain, that is includes some energy cost.
It really is excellent.
on dry beans v canned beans
Absolutely no comparison! In any cooking method, the energy cost is a few cents, but cooking from dry is 6-8x cheaper.
Or dry beans vs canned beans; does the cost of boiling the beans actually bring the cost up to be equivalent to canned beans?
Nowhere near, at least in a a pressure cooker. An electric pressure cooker uses 1KW when the heater is running, and you cook the beans for about 35 minutes. The heater doesn’t run the whole time but even if it did, that’s around 0.6 KWH at most. And you would normally do a bigger batch than you’d get in 1 can of beans. I have been wanting to measure the actual power usage sometime.
I don’t have a pressure cooker and cook beans on an electric stove, but I imagine it’s similar
On a stovetop you have to soak the beans overnight and then cook them for at least an hour, so energy usage might be higher, idk. OTOH the batch size compensates for a lot.
I very highly recommend getting a pressure cooker for this. Not only is it cheaper energywise and requires less planning ahead (don’t need to soak beans beforehand, much shorter cooking time), but you don’t have to keep tabs on a pot for hours. You just pour in the beans water and salt, press a button and come back later whenever you’re ready. Especially good for Garbanzo beans, which take a ridiculous amount of time to cook on a stovetop.
I’m not sure where you are, but I think homemade bread is not as bad for you as mass produced.
Dry beans weigh less
On the dry beans vs canned beans issue, I am firmly in the “it depends” camp. If you don’t plan your meals ahead of time, then dry beans become difficult to cook as you need to soak them overnight and take much longer to cook. The price of dry beans can be significantly cheaper, but strangely, not so much at a normal grocery store. I found that buying dried beans in bulk or in large bags is wildly cheaper, but most standard grocery stores (in the US) don’t offer them like that so your savings are minimal and don’t justify the the extra prep to me.
I think I did napkin math once that included cost of labour, and surprise surprise, mass production works. Just the energy is a good point too, though.
It sounds like energy pretty cheap right now. But, it’s also artificially cheap unless you have a lot of renewables on your grid, and somebody somewhere is going to pay for those emissions.
I didn’t do the math for bread - maybe I should reconsider that one, per the other users here.
No, but I do try to keep prep and cleanup times to under 1 hour for breakfast and lunch combined and 1 hour for dinner.
