Castor, Radioactivity, Green Energy, Kraftwerk

[diode]

Le 6 nov. 2010 à 18:54, Peter Korsten a écrit :

> But seriously, renewable energy is not yet a replacement for neither 
> conventional nor nuclear power stations. 

To Jay:

You can be self sufficient with a small installation if you lower your need a lot. It's not impossible, depends of the house and about what you're fine with dropping out. With more need, you'll need a mix of solutions.

Some basics (I'm rather lettered in this, damn politics ;) and I've searched a lot for the cabin in the Alps)

- solar: prefer thermic to voltaic, works everywhere, everyday, even in Sweden. Voltaic can be really tricky and easy to misinstall. Now, a good install in Malta should be rocking. ;) But it costs in voltaic to be powerful, so think more as sustainability/emergency than day by day full load especially if you can mix.
- Wind: besides regulations, it's better to invest with neighbors, to have a taller/more powerful windmill (for example, 25-30 meters high instead of 12, and 10KW instead of 1,5). There's big DIY models, with courses to learn how to make them by serious people or commercial ones (and a lot of crap). In Malta, if you have a decent place, it should be a good solution for most of the time (near sea, so lots of wind (if you have regular 60 km/h wind, it's the jackpot, the windmill SHOULD be taller than 10 meters, the higher the better, don't waste time with other models than horizontal axis/3 blades (vertical just don't work and the number of blades is not very important for electricity -3 is an optimum-, it is to pump though), It should NOT be on the house, definitely, for the safety of both. Best position in short is at least as far as it's high of trees/house/whatever obstacles there may be. Spend time studying wind in your place (at least a year) at the high of the fan, it's a good investment but first, have a look at a wind characterization (wind compass) by the nearest meteorological station, if it's very irregular, or no major wind, or too weak, think about something else than wind power. There's a lot of mad scientists with miracle windmills out there, be careful. The typical windmill works properly installed in the right place (if it's not crap of course)
Small windmills are "toys", think "big" so at least a kW or more, and the more is the better, especially if you can resale.

The key to windmills is regularity, a good strong wind and no turbulences. It should be high, with a good regulation system and at the right place. Don't believe the figures of the manufacturers, it's usually a bag of stupidities. And it's what's produced at 40-60 km/h that counts, not 10. Compare with the wind compass and the measures you'll be able to make in situ at the right altitude.

Avoid any model that is promising you to go beyond the Betz limit… A serious windmill has an efficiency of 40-44% or less. More is NOT serious. http://en.wikipedia.org/wiki/Betz'_law

One thing to know : well made windmills don't make much noise, especially since the last years.

For insects and bats, have the fan painted accordingly (it's something under study right now so I can't be more accurate, to care of the real ecological issue of windmills)

- microturbins you need a decent source of water (say some l/s) and a fall of a few meters, I'm not sure Malta is the place for it…
- biomass: I'm not competent
- nuclear fusion, well, it's not working still.
- water engine, let's be serious ;)
- Vacuum energy: you have a working patent you're rich!

For Malta, without knowing more, I'd be for a mix of solar thermic/voltaic (hot water all the time, electricity when the wind fails) and a windmill (the electricity workhorse) if the place can accept one. And batteries, it can help ;) But voltaic will need less day by day work to maintain than a windmill (that you have to care of regularly, is out when no wind or too much -more than 90 km/h-. Voltaic lasts about 25 years, a good windmill regularly pampered is out there for about 50 years. If the place is not great for a windmill, drop it and go solar all the way. You'll avoid some disappointments.

If you start from scratch, think about a low voltage system, with lights in 12 or 24 V, and eventually the fridge. It'll be easier to handle for you. But if you produce more than sufficiency, go 220 V to sale to the regular furnisher if possible, even if the regulations can be a little costlier.

It'd be a good idea to see if there's a little made by the local electricity furnisher in direction of renewable, as an installation plugged in the general system would more comfortable and you could sale your overproduction. But as here regulations apply as for the permits for the windmill, you'll have to dive into the Malta legal stuff.

I've written down all I could think of without drowning you, if you have any question, just ask.

Denis H]
No LOPPSI!
No HADOPI!
No ACTA!