Tuesday, October 21, 2014

Alternative Energy

I've been fascinated by alternative energy options for a long time. My favorite alt energy system is the biogas digester, because it uses a fuel that is waste for most people (and, yes, the biogas digester can be fueled with humanure).

What's fascinating to me is that one of the complaints about our feedlot system is that there is no safe way to dispose of the copious amounts of waste, and I often wonder why they aren't using that waste to power the local community ... but that's another post.

My ideal solution for powering my home would be a combination of solar and wind to charge a battery bank for our electricity and biogas for water heating and cooking.

Ideally, we'd modify our existing septic system to be a biogas digester, but I'm actually told that's not possible, because the septic system is designed so that there isn't a gas build-up, and gas build-up is exactly what one wants with the biogas digester.

I've seen several videos on YouTube for DIY biogas digesters. Most of them are clumsy and messy looking, but this one was actually neat and tidy. What was also compelling about this design and model was that:
1. a woman assembled it; and
2. the woman filled it wearing a white shirt.

I think I could actually build one of these on my own. The set-up is pretty simple, and we, definitely have the fuel.

We couldn't use a biogas digester here in Maine for most of the year. In order for the microbes to work at breaking down the fuel and turning it into gas, the temperature needs to be around 64°F (or >18°C). Basically, I wouldn't be able to use it right now, because it's too cold - but given that my goal would be to use the biogas for cooking, primarily, it would actually work out perfectly for us. During the winter, I cook on the woodstove. During the summer, I cook inside on our electric stove, and we notice a marked increase in our electric bill during the summer.

The point is that I need an alternative cooking fuel more during the summer than during the winter, anyway. It would be worth it to have the digester for the free cooking fuel, even if we could only use it from May to September.

How about you? Would you build a digester? If not, what's your preferred alt energy?


  1. Seeing that it's a sealed system, technically you could put the biogas system in the house (basement) and have it year-round. Or what's the in-ground temperature? It's pretty close to 64F, as I recall.

    1. I'm sure there are ways that it could be done, even here in Maine, but I believe the underground temperature is 55° - a bit cooler than recommended for optimum efficiency for biogasification ... but perfect for storing cheese, certain vegetables/fruits and curing salamis ;).

      I don't have a basement, and if we were to bury the biodigester, we would have to be sure that it was below the frost line - at least four feet deep.

      Probably our best option is a combination of systems - a biodigester during the summer, and wind or solar or steam from our woodstove during the winter.

      There is no one best system, and I'm really just imagining my options.