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I'm surprised a little that this was the best idea to provide energy for the home. I would have thought evacuated solar collectors for hot water, solar photovoltaic for electricity with some deep cycle batteries, and wood fire for indoor thermal would be more reliable and efficient.

It looks like this is in southern Chile, though, maybe the solar incidence so far from the equator doesn't allow it? I wonder how reliable the source for the stream is.

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Microhydro is extremely reliable and has a very low variability compared to solar in a similar situation. If you have running water with sufficient vertical head, it's almost certainly the best option for small-scale power generation.

I've looked into it for myself, and it's something like 95%+ availability of full working power, which is probably better than the public power supply in that part of Chile! Pretty amazing stuff, and the fact that he can wind his own transformers(!!) is certainly going to make it a lot less expensive.

Sure! It's amazing work, but with the electric needs of the cabin I just think it might have been almost too high a quality of power (assuming the source isn't subject to drought and deep freezes aren't a problem). The cabin looked like it was in a clearing, so I think he could have put in something like http://www.wholesalesolar.com/solarpowersystems/workshop-3-o... (9kW) for a similar price.

edit: please take this in the context of my first comment. I think he should be taking care of more of his thermal needs with non-electric sources, neither solar nor hydro. Also, nobody's load is continuous, and real life load correlates with daylight hours. Anyway, I'll stop, it's a really cool project and don't want to take anything away from it.

That's only 1700 Watts continuous, assuming the sun matches whatever they used for the spec (and it sounds like he is getting at least 4 KW even during the winter).

Yeah the effective power at the cabin is 7kW, you'd need 3 of those to mimic it, and I guarantee you that the microhydro was significantly less expensive than a single one of those. His whole system probably ran $10k or less considering he's winding his own transformers and doing his own electrical work.

That panel is advertised by it's manufacturer to produce up to 1222kWh/month. That's just 1.7kW continous. To match the 4 nozzles, you'd need 5 of them, and that's assuming no clouds.

The nominal power values for wind and solar are peak values. When comparing with other ways of making power, you can in general divide them by 5.

On top of that, he'd need a ~100kWh battery (cost >$10k) just for the day-night variation, more if he wanted to deal with days when the sun doesn't shine.

Solar power is awesome, but it's actually a really bad way to produce power small-scale when off-grid. It's used because often it's the only way, but if hydro is an option, it's always much better.

To use solar properly, you really want to either use it to run industry that can be adjusted to fit the output, or you want to spread it over a large geographical area to smooth out the peaks and back that up with something adjustable.

> real life load correlates with daylight hours

This is only true reasonably near the equator. Where I'm now, the sun won't be up before I leave for work and it will be down again before I return. There is basically no load when the sun is up, except on weekends.

The hydroelectric system may also serve as a energy storage. The surplus of day-time energy from a solar power system may be used to pomp water upward for later use in the electro-hydraulic system. So those systems can therefore work combined, not in mutual exclusion.

To turn solar power into a reliable source of AC power off-grid you need an electricity storage system that will easily cost more than the PV installation itself. Micro-hydro, if available, provides a very high capacity factor output without the need for an inverter / PCS / battery.

If you have space for a pond but no reliable flowing stream, you can use the pond as the battery for your solar panels. Each kWh of storage in a 2m deep pond will take about 100 m^2 of area. A typical American house would use 6 kWh or so per night, but probably someone building a system like this would use less.

Calculations: https://www.google.com/search?q=12+kWh&ie=utf-8&oe=utf-8&aq=...

That's actually a surprisingly large pond!

I don't have enough flat space for that. I do have a large mountain, but there's no room for ponds on that - more's the pity, no streams nearby either.

Does the pond volume/kw vary if the height of the pond is higher?(so the water has more potential energy)

Or, scrap the solar panels, fill that pond with salt, and make a solar pond. http://en.wikipedia.org/wiki/Solar_pond

I've seen quite a few micro hydro schemes here in Scotland - hills and water being two things we have plenty of!

Microhydro is pretty reliable. I've seen quite a few micro and pico hydro plants in mountainous regions of Karnataka (an Indian state) that supply power nearby villages[1]. They're pretty popular in Himalayan states as well[2]. Ministry of Energy subsidizes them[3][4].

[1]http://kredlinfo.in/hydrostat.aspx

[2]http://www.ureda.uk.gov.in/pages/display/131-micro-hydro-pro...

[3]http://www.mnre.gov.in/schemes/grid-connected/small-hydro/

[4]http://www.iitr.ac.in/departments/AH/pages/Activities+Short_...

coldarchon 19 hours ago | link [dead]

Maybe you can answer me a question I had after reading all of it; How are those micro hydro plants in the mountains protected from frost? -----

@coldarchon,

Somehow, your posts are marked as [dead]. You may want to shoot a mail to pg.

Regarding the frost problem, sorry, I'm not sure how that's handled in cold regions. The ones I've seen are from south-west part of India, which has tropical climate[1].

http://en.wikipedia.org/wiki/Western_Ghats#Climate

He is close to a volcano, and on the edge of a tectonic plate. He could likely extract geothermal energy for heating purposes by merely drilling a few meters into the ground, which would greatly reduce the power load on his plant in the winter. I wonder why he didn't go that route - he must have though of it.

In areas where I've trekked in Nepal they used to have solar and wood and it didn't work very well - not much light, deforestation etc. They now mostly have mini hydro - one plant per village - and it works pretty well.

I'm guessing somewhere around Temuco based on the Llaima Volcano being in the background - absolutely beautiful area of the country (but then again, it's hard to find a part of Chile that isn't beautiful!)

looks beautiful indeed. how much would 40 hectares of land round those parts go for?

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