OT -- off grid power systems

I'd like to chat offline with someone who has installed a solar array system that feeds your load AND backfeeds to the grid {"meter backwards"}.

And/or, I'm looking for a pointer to forums [formi??] centered around such.

Reply to
David Lesher
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Weve been off grid for some 39 yrs. used diesels for power generation, on demand systems by Lister, called the startamatic set up.

5 yrs ago found 3 tons of nicad alkaline( sodium hydroxide ) batteries. so then invested in an 3kw "outback" US system of charger/inverter. Been in use for 6 months and has proved very efficient. Next step is to use one of our 6/1 diesels running on straight vegetable oil as a dc generator to eliminate the use of fossil fuel. Will need to make a suitable alternator aka windmill permanent magnet type. as for solar, this could be a possibility but due to the poor UK weatherm sunshine is not reliable enough for us. also the cost of connecting to our uk grid is prohibitive, due to the distance. Google for outback there the best right now for what you want. Ted Dorset uk
Reply to
Ted Frater

I though UK sunshine was measure in inches per hour...!!!

I built a couple of the MEN style conventional wind turbines a few years ago. They work OK but I'm thinking of building a couple vertical vane units to eliminate many problems that you have with conventional wind turbines. No need for a wind vane or directional control. Should be able to put the actual generator at the base and use a simple shaft up to the vanes. MUCH easier service that way.

With all the Amish around here now I might even have a market for them! Most of them use an automatic diesel system for the milk house to provide vacuum and cooling and air power.

Reply to
Steve W.

Re Vertical axis wind turbine, My son ,( now 26) researched, designed and built for his senior school CDT final year project some 10 yrs ago a 10ft tall vertical axis 3 blade darius windurbine for just this purpose. The intersting bit was the blade making. If you like I can write up what we did.We still have all the. bits somewhere in a shed. we used an all metal construction for them.very strong and simple. however the advantages of this type of wind turbine are outweighed by its poorer efficiency than the horizontal axis type.To get the same power output they need to be twice as big. Ie there only 50% as efficient as the other type.Sorry to say. whatever anyone else may say. In 15mph wind tests it spun well , tho it was out of balance due to blade inaccuraces We also had a neibour who built a horizontal axis turbine some 20ft dia. using 4 3ft dia cones. this was effectively a drag machine with the torque output being the difference between the drag of the down wind going cups and the upwind . going ones. Never heard how he got on. Been dismantled some time. Can find out again if you would like to know. Ted in Dorset UK.

Reply to
Ted Frater

A few offgridders have posted on alt.energy.homepower but the level of technical info was far lower than here on R.C.M.

jsw

Reply to
Jim Wilkins

Your request doesn't seem to be an "off grid" request, but here's my reply.

a.s.photovoltaic is one newsgroup that deals with things solar-PV. You have to put up with some guys who like to beat eachother up, but if you persist, you can learn some things.

I have two friends within 50 miles of me who have put up 3Kw and 7Kw pv systems recently. They are both grid tied. One cost about $40,000 and the other cost about $70,000. Rebates pay about 1/2 of that back in Wisconsin. They both supply their local load and do grid tie, but if the power goes away, neither of them generate for local use. You have to spend more money to get that feature, I am told. Also, neither one of them went with batteries. We have a pretty reliable grid here.

Pete Stanaitis

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David Lesher wrote:

Reply to
spaco

Steve Spence, at Greentrust (he's got a web page

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) might know that kind of thing. He's big alternative energy guy.

Reply to
Stormin Mormon

On Sat, 27 Mar 2010 05:39:48 -0700 (PDT), the infamous Jim Wilkins scrawled the following:

I'm interested in this stuff, too, and found the same lack of in-depth info on AEH depressing. The breadth and depth of info found here is wonderful. Great group.

-- "Not always right, but never uncertain." --Heinlein -=-=-

Reply to
Larry Jaques

Try searching Backwoodshome.com. It is a magazine for self-reliant living. You can search their back issues for past articles. It is a great magazine. Tons of solar articles over the years.

Reply to
Jesse

Try here.

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You might also search alt.energy.homepower looking for posts by Clarence Dold. Or just post your question there so that he and other grid-solar types will see it.

Wayne

Reply to
wmbjkREMOVE

That's crazy! They are metric.

Reply to
cavelamb

On Sat, 27 Mar 2010 07:02:23 -0700 (PDT), the infamous Jesse scrawled the following:

Thanks. I'll give 'er a looksee.

-- "Not always right, but never uncertain." --Heinlein -=-=-

Reply to
Larry Jaques

That sounds similar to the

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systems sold here in the PNW. I called them wanting a system that feeds back into the grid if there's an excess *and* also provide us power if the grid goes down. No can do, she said.

If your friends systems are capable of this, I'd really appreciate the contact info of that company.

Thanks Pete,

Newb

Reply to
nobody

The problems I see of feeding back into the grid are multiple. Matching frequency precisely. If there is a down line in the grid, and the power is turned off for repairs, does the lineman die because your grid came online and fed power backwards? Or your controller burns up, because the grid looks like a direct short when no power in to the grid.

Reply to
Bill McKee

You'd definitely want a UL-listed commercial product, which solves all those:

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jsw

Reply to
Jim Wilkins

All true. But grid-tie systems are out there, in use.

The question is: what's available in dual mode systems:

a) Grid-tie, feeding power back IFF there is utility power.

b) Power failure mode: supplying the house from solar and battery when the utility goes down.

Reply to
David Lesher

All things that need to be considered and engineered in. The frequency matching is easy, doesn't even take fancy computer controls. One way to isolate the home side from the line is to use the line frquency as the determining factor. It has to match that anyway. Absence causes a mechanical trip and isolates the home side. Require a manual reset AND line voltage presence to link again. Presumably, if line voltage is there, there's no lineman handling wires to toast somewhere.

What this sort of thing requires is a battery set, cells somewhere between aquarium and swimming pool size. And all the maintenance and proper venting that requires. Nothing like a hydogen explosion to ruin your evening. Your charging device(s) would charge the batteries, as and when possible, and a whopping big sine-wave inverter would provide the AC, with synchronization provided by the line. Battery cost is usually the killer here, they start going downhill as soon as they're wet, 5-10 years would probably be a good lifetime. Wonder if Edison cells would have a market these days? Railroads used them in a lot of high-reliabiity, low-maintenance roles.

Stan

Reply to
stans4

Nickel-iron cells are available, but look at the price:

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can buy deep-discharge lead acid batteries for

Reply to
Jim Wilkins

Yes it is, there's a growing industry relating to that in Europe too. Germany is setting up solar systems on homes and buildings just for this purpose, mini power generation systems feeding the grid for distribution to where it's needed. That technology is here.

Exactly. If anyone knows a company that can provide both features, I'd sure appreciate their contact info.

The way I figure this is that it would be a shame to have an excess of solar generated power go to waste. I plan to over build this system in order to ensure we'll always have as much as we'll need.

Thanks,

Newb

Reply to
nobody

...

A link is in my previous posting.

jsw

Reply to
Jim Wilkins

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