Solar power possibilities for Northeast?

jbos333 · August 17, 2009, 12:50:58 PM

Hi all, I was wondering if the solar gurus here could answer the feasibility of this. I have, in other posts, asked how far I could extend my current electrical service. Well, the answer is pretty much NO due to voltage drop.

So, I have gotten a ballpark price to install a new service, in addition to my existing service, and it wasn't very pleasing. I realize it probably is still cheaper than solar, but I would like to try to be less dependant on the "grid" in the long run.

Here's the deal.....I have a 200 amp service running to my utility building approx 400 ft. off the road. My ideal building site for a cabin/small (800-1000 sf) home is another 500 ft. beyond that. I was wondering if it would be possible to locate pv panels and a battery bank about 1/2 way between the two and use that to power the "cabin" and still maybe be able to grid tie it back to my 200 amp panel? I could presumably run my well pump off the existing service so that wouldn't be a draw on the solar.

Also, because I'm in Western NY maybe I don't get enough sun to make it worthwhile?

jbos333 · August 17, 2009, 12:57:08 PM

Oh yeah, forgot. Wood heat, propane or NG cooktop, hopefully electric fridge, propane or NG clothes dryer, hopefully electric washer. I do have enough room in my "utility" building if I had to insulate a corner room for washer/dryer to reduce the electric load I could. I would just have to pretend I was going 500 ft. to the Laundromat. Can you tell I live alone?

August 17, 2009, 01:27:35 PM

Put the power generation closest to point of use so that way your dc won't have far to travel before it's used so less line losses. Also have the inverter at the point of power generation so you can run AC the "longer distance". I hope this is something that might be helpful? I will add I'm certainly not an expert on electrical.

Jeff

jbos333 · August 17, 2009, 03:00:10 PM

Just got off the phone w/a semi-local solar/wind guy. They offer solar/wind combo systems. They have a "starter" solar/wind setup contained in a shed for around $16k that they said would do about 3kw in spring/summer and maybe 1.5kw in fall/winter. I looked up my daily useage at my "in-town" house and it's 3.8 kw avg. daily. I can probably shave some off of that, though, at the "cabin".

glenn kangiser · August 17, 2009, 11:27:35 PM

Sounds low to reasonable - any specs you could post here for that setup? There is good and bad out there.

August 17, 2009, 11:32:34 PM

Depends, is the answer. Lots of things to factor in.

Our system, which will go active next weekend if all goes as planned, has the PV array 300 feet down the hill out of the trees. We have three 208 watt panels. I used 2 gauge copper wire/cable to carry the 72 volt, 8 amp DC up to the cabin where the charge controller, batteries and the inverter are located. Placing the batteries and inverter down at the panels was a thought as speedfunk mentioned. Why did I not do that?

One reason was that the calculated maximum AC amp load would have necessitated about the same size wire anyways. Mind you that is with using a higher DC voltage than many systems use. If I had set up the PV panels in a 24 VDc combination as many do I would have needed even larger wire; huge impractical wire. If that's not clear I'll try to explain. At 72 VDC there are only 8 amps maximum (612 watts) going through the wires. The DC power slowly charges the batteries. With the inverter down at the hill bottom there would be 120 VAC through the wires. However, if the microwave, toaster, TV and some lights, plus maybe a fan or tool battery charger were all in use at the same time that could total a load of 16 to 20 amps. (@16 amps = 1920 watts, 20 a ps = 2400 watts). The DC power coming up the hill would hopefully be fairly continuous on a nice sunny day versus the AC power would be more fluctuating, more peaky. However the potential for even short higher wattage loads means to me that to be efficient the AC wires would still have to be large.

In the end I chose to keep the equipment up at the more convenient cabin end.

Regarding your power use. Appliances like washers, electric dryers, refrigerators use a lot of electricity compared to CFL lights and LCD TV's. Having those loads in an off grid system means you will need more panels and more storage batteries if you expect to make your own power for them.

In some states you can sell excess power back to the utility. That way you can dispense with the batteries and use the power grid as your battery. Of course that doesn't help you when the grid goes down.

As far as the system in a box goes, sometimes they can be the way to go, but when you toss unusual variables into the mix their usefulness may fade. Great cable run distances are one of those things that can be a problem. Not all charge controllers offered in "kits" can handle the higher voltages like we've run, for example.

I'll be glad to help out in whatever ways I can.

MD

MountainDon · August 17, 2009, 11:38:11 PM

Here's a kit from some folks I've bought from.

http://www.affordable-solar.com/solar-power-system-off-grid-3075-watt.htm

3.1 Kw rated at just over $19K. Click on the Kit Products tab to see what you get. 15 x 205 watt panels and Outback charge controller, Inverter and peripherals. Good stuff.

Do a comparison to what the locals are offering.

MountainDon · August 17, 2009, 11:44:02 PM

BTW, how much does the local power company want?

Mine wanted $55K to bring a line in about 34 mile in mountainous, rocky terrain. Had to be underground.

jbos333 · August 18, 2009, 07:43:53 AM

Hey thanks for the replies everyone!

Don, I am in the process of getting a solid number on the grid power install, but it looks like around 10k- my utility won't supply the wire for underground and won't install underground; I have to hire privately for this.

The 10k figure is based on about 1000ft to my proposed site. I already have "grid power" underground to my utility building w/a 200A panel, meter at the road, about 350 ft. in. I don't expect you to remember, but a while back I posted asking if there was any way I could extend the existing service another 500 ft or so and the overwhelming answer was "NO WAY!"

I looked at my daily useage over the last year at my "in town" house and it was 3.8 kwh/daily average. That includes electric roof heat tape in winter, dehumidifier all spring/summer, and all my garage loads- battery charger, welding machine, etc. Now I'm sure I could trim that figure down a bit for the "cabin", and maybe run some of the larger loads from my utility building grid power- well pump, and all the "shop" stuff for example.

And, I was wondering if I could centrally locate the battery bank between the two buildings and possibly utilize grid power to supplement the PV and wind on those overcast or winter days.

I know, crazy ideas! But if I can spend a little more now to avoid paying on another meter (min charge 17.00/mo even if using 0 kwh) and of course, I can't see electricity going DOWN in price anytime soon, then maybe it's feasible?

Glenn, I didn't really see any specs on the self contained system. I think they will make them to suit your needs. They are using them locally now for construction site power. Canadice Construction is the company name.

August 18, 2009, 08:02:52 AM

For those who posed the question, NY state is a net metering state.

I found an article of someone installing wind turbines for 4-5K in a paper in Otsego county this year. If I can find the article again I will dig it up. If you can get away with it, I would definitely go for the wind turbine over solar for your location. The winds are high and powerful coming off the great lakes and the sun is next to nothing in the winter. It would probably have a quickest payoff.

Don't forget to add in the maintenance costs vs. the power cost for a 10 or 15 yr period.

Windpower · August 18, 2009, 09:03:32 AM

It is important to do a wind assessment

hire a pro if you are in doubt

you need at least a 10 mph average at your site

generalized wind maps can be very far off of what your particular site has

the wind map average for my general area are about 8 to 9 mph

but since I am on a hill I get alot more ~ 12- 13 mph average

the average speed makes a huge difference since the energy goes up as the square of the speed

MountainDon · August 18, 2009, 09:37:45 AM

Windpower is right on the money on that. Wind can be very local. If you have the time and the money you could also install your own weather station and log the data to a computer. I had that going for a few months and it indicated wind power was an iffy proposition for that spot unless I had a very high tower to get above the trees.

jbos333 · August 18, 2009, 09:50:08 AM

Good point about the wind.....that self-contained unit for 16k was a solar/wind combo.....they said without wind option about 14k but definitely recommended wind at least as a supplement esp. during winter months.

I will have to investigate a "weather station" for my site and record some data.

Windpower · August 18, 2009, 10:02:53 PM

2 K for the wind option ?

major big flag

August 19, 2009, 10:53:15 AM

The "wind option" on this is just 1 of those small turbines attached by a pole to the "power shed".

speedfunk · August 19, 2009, 12:29:24 PM

Quote from: Squirl on August 18, 2009, 08:02:52 AM

I found an article of someone installing wind turbines for 4-5K in a paper in Otsego county this year. If I can find the article again I will dig it up. If you can get away with it, I would definitely go for the wind turbine over solar for your location.

If you do dig it up that would be awesome. We are def going to looking at a grid tied wind/solar combo net metering setup in future!

Quote from: MountainDon on August 17, 2009, 11:32:34 PM
Depends, is the answer. Lots of things to factor in.

Our system, which will go active next weekend if all goes as planned, has the PV array 300 feet down the hill out of the trees. We have three 208 watt panels. I used 2 gauge copper wire/cable to carry the 72 volt, 8 amp DC up to the cabin where the charge controller, batteries and the inverter are located. Placing the batteries and inverter down at the panels was a thought as speedfunk mentioned. Why did I not do that?

One reason was that the calculated maximum AC amp load would have necessitated about the same size wire anyways. Mind you that is with using a higher DC voltage than many systems use. If I had set up the PV panels in a 24 VDc combination as many do I would have needed even larger wire; huge impractical wire. If that's not clear I'll try to explain. At 72 VDC there are only 8 amps maximum (612 watts) going through the wires. The DC power slowly charges the batteries. With the inverter down at the hill bottom there would be 120 VAC through the wires. However, if the microwave, toaster, TV and some lights, plus maybe a fan or tool battery charger were all in use at the same time that could total a load of 16 to 20 amps. (@16 amps = 1920 watts, 20 a ps = 2400 watts). The DC power coming up the hill would hopefully be fairly continuous on a nice sunny day versus the AC power would be more fluctuating, more peaky. However the potential for even short higher wattage loads means to me that to be efficient the AC wires would still have to be large.

In the end I chose to keep the equipment up at the more convenient cabin end.

good thinking Don, that makes a ton of sense. A lot of this does depend on situation. Thanks for offering this very useful description of your situation and how you designed around it.

Squirl · August 19, 2009, 03:37:20 PM

Quote from: jbos333 on August 19, 2009, 10:53:15 AM
The "wind option" on this is just 1 of those small turbines attached by a pole to the "power shed".

If you have any trees or buildings within 300-600 feet, with a wind turbine that close to ground level, 2k seems like a rip off.

Speedfunk,
I will try and dig up that article, but I think it was from one of the free local papers from April.