Granny's Homebrew Algal Biodiesel
Biodiesel production aims to use vegetal or animal oils as a renewable substitute for ordinary diesel. Supposedly the UK is presently committed to deriving at least 5% of all transport diesel from biodiesel by 2010. It has powered jetflight and (when mixed with ordinary diesel) UK trains. It would be interesting to start probing the possibility of homebrew production.
The Hackspace doesn't have a field, so we have to explore algal biofuels.
Whilst it would be wonderful for the project to eventually be able to harness enough solar or heat energy to not require a net input of chemical or electrical energy, it's not likely that we can either source enough light or drive the reactions efficiently enough for this to be feasible.