Someone (I can't remember who...sorry) Suggested a biodiesel generator for the nursery

Is this a practical option - does it provide electricity? How would I use that to heat the nursery?

Would it need filling like a car engine or would it be attached (like an LPG tank)?

Any ideas?

If you use biodiesel for heating then you must be able to either get the duty back or not have to pay it in the first place. It would be unlawful for you to have to pay this duty.

We use biodiesel that we make ourselves to heat our caravan whilst we build our house. We use hot air blowers that are sold for trucks and boats and just plumb into the diesel tank to produce hot air (lots of it). It costs us about 13p a litre to make our biodiesel - no tax is due as it's a heating fuel. The heaters come in up to 5kW sizes.

You could run a diesel generator on biodiesel, use the electricity for lights and use the waste heat (any engine has a lot of waste heat) to heat the building. However, diesel generators are fairly big and expensive (and not always so quiet), and I've not seen one that's designed to provide domestic heat as well. That said, I'm sure something like that should exist as it's an obvious use of the heat generated.

Converting anything to electricity is always inefficient. Electricity to heat is efficient, but biodiesel -> electricity -> heat overall is pretty poor, especially when you consider that biodiesel can be made to produce heat directly. Your best bet is to use electricity only for the necessary things - almost all successful green power generation schemes (wind turbines, solar PV etc.) start with reducing electricity consumption as much as possible before using generators.

Do a search on 'CHP diesel' (Combined heat and power, which is what you want, and diesel generators will run on biodiesel without modification, though you might want to check with the manufacturer to ensure they are covered). You might find something interesting.

Blimey, if you're making biodiesel for only 13p/litre then CHP makes a lot of sense, to generate your irreducible electricity requirements and use the waste heat for space heating. But if you source your electricity elsewhere it makes even more sense to burn it directly as a biofuel for space heating.

It's difficult to get hold of the solvent you need (methanol?) to make biodiesel, too: and if you buy it in quantities large enough to be useful then your premises will need regular inspections for safety. Don't think you'd be allowed to store it anywhere near where you're looking after children.

For Katy's application, making your own biodiesel is not really an option. It's entertaining enough as a way to spend a day each month, but it consumes space, time and is a dirty process.

To be honest, biodiesel powered CHPs are probably not an option either - unless you have the time and inclination to tinker with engines, they are not practical. You can't just press a button and reliably have energy, unless you've spent a serious amount of money on a ultra-reliable 24/7/365 set-up which I'm sure would be out of most people's budget.

The use of palm oil is an issue, but unless you're running a commercial operation, most bio-diesel producers don't pay for their oil - they just take away oil for free. It's not encouraging chip shop owners to use palm over rape seed - that is entirely their ethical choice.

I agree re H&S: I'd rather not have caustic soda and methanol around 'on the shelf', but methanol is not hard to find - ask your local sppedway, grass-track or sprinting club.

I read that there's one Pacific paradise island whose fuel is entirely supplied as used chip fat from the cruise liners.

Maintenance nightmare though..... Unless you are a stationary diesel fanatic, you are going to be paying out for a full service every....how much would you use it? If a lot, that's a lot of service calls.