Please make sure you read these reviews in order, so if haven’t read part 1 you need to reselect an earlier posting.
Swen66: What do you mean by being energy neutral?
TM reply’s: “Energy neutral means you will not use up any energy availability by running or operating the building. The second law of thermodynamics says power to heat and heat to power is not totally reversible. This means if you turn work into heat, you can’t take this heat and turn it back into work. You will come up short. This portion of irreversibility is called availability in thermodynamics. So then, if you take a fossil fuel and burn it, you can power a car, or do many things. In this process you will lose some work that won’t be recoverable. So energy neutral means using as little availability as possible. Techniques like geo-thermal are a way to utilize renewable energy sources. Ideally, when you had excess heat, you could figure out some way to turn it back into work. It’s already said that you can’t get 100% conversion. Bottom line, it’s a storage issue. In Illinois, when we have heat, we have more heat than what we want. When it’s cold we’re colder than we want to be. We need to take these elements (hot or cold) and store them until we actually need them.
Swen66: Kind of like a BIG battery
TM: So in the summer time I pump up my heat battery and in the winter I pump up my cool battery. So when the summer comes I can turn on my cold battery and use some of this negative heat that I’ve stored, but also store some of the excess heat.
Tags: availability, EIGERlab, energy neutral, thermodynamics
