Solar panels to power your LEAF...or other EV and home...

[Gavin]

This shows the insolation for various cities across US. You have a low of 3.1 in Chicago to a high of 6.7 in Albuquerque among bigger cities. This is the average in a year.

http://www.solar4power.com/solar-power-insolation-window.html

Albuquerque...we're number 1...sweet.

Every new home in Albuquerque should be required to have solar...insane that we don't...

Was just out side with a compass...our roof is almost exactly due south...181 degrees...nice

Have one more estimate this week...hope to have it up and running by first week in July...

Gavin

 

[garygid]

181 degrees ... Magnetic, or True south?
(only 9 degrees different there)

 

[Gonewild]

My system facing south and it is getting hotter so my power now is 33.5 to 34. My 5.16k system only puts out max 4500 to 4900 watts at this temperature.

Actually, it's the light, not the heat, that matters. Ignoring cloud and rainfall patterns you can expect your highest output in late June and your lowest in late December. Locally, we tend to get more rain in January than December, so my lows come then.

Oh, wait. Snow? I have no idea what effect that has, as we've never seen it here. Where we are, heat is our enemy. Our utility meter runs backward most of the spring (building up to June), but forward much of the summer (due to air conditioning).

I know what I meant was yes power goes down as the heat goes up. But Sunpower panels are 10% better in the heat the other panels and they work at lower light level as well.

 

[garygid]

Gavin,
What is roof slope?
Slope approximately equal latitude is near optimal for spring and fall, a bit too flat for winter and too sloped for summer.

Optimum depends upon being Inverter-limited or panel-power limited.

When you get the estimate, ask them how and where they would configure a larger system.

If you are really space-constrained picking panels that are really more efficient might be an option.

 

[LEAFer]

Any thoughts on ground-mounted solar systems ?

 

[mitch672]

Any thoughts on ground-mounted solar systems ?

from what I've read, the mounts cost more, and there area manually adjustable ones, trackers (expensive), and fixed angle mounts. Roof mounting is usually the least expensive option, and also usually the most immune to shading problems because the panels are higher and usually clear of the tree shadows

 

[Cacti]

Any thoughts on ground-mounted solar systems ?

Yes, ground mounts are more expensive. Our roof was not an ideal option so we opted for a ground mounting array. Ground mounts do have some advantages:


1. Cooler panels
2. Easier to clean and remove snow
3. Can align them to true south

Link to picture, scroll to post #45

http://priuschat.com/forums/environmental-discussion/57267-our-solar-electric-panels-done-5.html

 

[mitch672]

Our 5.28 kW array produced 653 kWh (average 21.77 per day) for the month of April 2010. We are located south of Boston.

See post above, I am investigating "sunrun", as I plan to move within the next 2-3 years, so I am not willing to put out a large sum of cash right now. Sunrun does solar financing (and power purchase agreements), and the system can be transfered to the new owner, or they will remove it...

http://www.sunrunhome.com/why-sunrun/compare-sunrun-solar-plans/sunrun-power-plan

It just makes no sense to spend $40K, even with a %30 federal rebate if you are planning to move within a short time.

and, I am also South of Boston, who installed your system? I have a quote from "NextAmp" for a 24 panel enphase microinverter system, thats the most panels than can fit on the southern exposure of my roof. Also cacti, maybe you could add your future Leaf (if you are planning on getting one I assume) to the google map thread we have, it looks pretty lonely in the Boston area for Leafers, just myself and one other person...

 

[Cacti]

Our 5.28 kW array produced 653 kWh (average 21.77 per day) for the month of April 2010. We are located south of Boston.

See post above, I am investigating "sunrun", as I plan to move within the next 2-3 years, so I am not willing to put out a large sum of cash right now. Sunrun does solar financing (and power purchase agreements), and the system can be transfered to the new owner, or they will remove it...

http://www.sunrunhome.com/why-sunrun/compare-sunrun-solar-plans/sunrun-power-plan

It just makes no sense to spend $40K, even with a %30 federal rebate if you are planning to move within a short time.

and, I am also South of Boston, who installed your system? I have a quote from "NextAmp" for a 24 panel enphase microinverter system, thats the most panels than can fit on the southern exposure of my roof. Also cacti, maybe you could add your future Leaf (if you are planning on getting one I assume) to the google map thread we have, it looks pretty lonely in the Boston area for Leafers, just myself and one other person...

Our first array (2.88 kW, 16-Evergreen 180 watt panels) was install by SolarFlair in May 2008
Our second array (2.4 kW 12-Evergreen 200 watt panels) was install by GroSolar in May 2009
Each array has a Solectria 2500 inverter

Yes, I am registered for the Leaf.

Cacti

 

[mitch672]

Checkout this nice no rack solution, I checked out "GroSolar", and they seem to be pushing this now... no rails needed, of course it only works with 1 panel curently made by Canadian Solar

http://www.grosolar.com/zepsolar

http://www.zepsolar.com/zepsystem2.html

http://www.zepsolar.com/

http://www.zepsolar.com/modules.html

nice that they eliminate the racking, but doesn't appear to be a way to use microinverters with it... no place to mount the inverter to from the looks of it.

 

[garygid]

I went with one SMA SB 7000US (7000 watt AC output max. "SunnyBoy") inverter (about $4000) instead of 33 x $200 ($6.6k) in micro-inverters. The reputation of the SunnyBoy inverters seemed excellent, and they claim high efficiency. But, there were arguments each way, and I was trying to make the decision 2 years ago, when the micro-inverter was rather "new".

Ground support structures can be relatively inexpensive if planned well, and the labor of placing panels is greatly reduced.

So, if you have the room, and the site has few shadows, it should be no more expensive than roof-mounted ... unless connection to the Grid AC is not nearby.

For safety, consider fencing, if needed, to limit access to the panels and the electrical connections.

 

[Gavin]

181 degrees ... Magnetic, or True south?
(only 9 degrees different there)

Well using my very scientific iPhone gs3 compass...
180 plus or minus 1, true north
172 plus or minus 1, magnetic north

this fits well with both companies so far telling us our house is basically perfectly north/south facing

slope of roof is 15%....sunpower company plans to place them flat, other company want to place them flat too, but their brackett system naturally adds 10% slope, so they would have the panel at 25%

Gavin

 

[garygid]

"bracket system adds 10% slope" ... does not make sense to me.
What kind of bracket system would "require" that?

If the panels are not coplaner, they have to be spaced to avoid shadowing the panel above.

Slope 15% is rising 1.5 feet in 10 (level) feet. So, a 100% slope is 45 degrees. You are at N 35º.

 

[scottsim]

44 200W Kyocera panels in two ground mounted arrays of 22...Today did over 60KWh....Wind turbine, Skystream 3.7, much wimpier...average has been just over 1.5KWh/day.

 

[Gavin]

I probably misunderstood about the naturally adds 10%...more likely he said "can add 10%"

ISYS Roof Mount is a flat roof solution that requires zero field fabrication, and can be installed at a rate of 2-3kW per man hour. The configurable design accommodates 0-30 degree module tilt and enables customers to maximize their project’s power production.

Unirac site


Gavin


I like that the bracket system is made in Albuquerque...and if we go schott panels, they are made here too...my city seems to be a solar hot spot...sweet, now if only we can get it to be an early LEAF release city.

 

[garygid]

Tilted panels on a flat roof:
Be sure they allow enough spacing so that the long winter shadows do not shade the row "behind".

Also, the bracing and panel mounting needs to be engineered for high wind conditions.

 

[hill]

It'd be nice if Nissan gave a closer delivery date to those who will be charging from PV. Seems it'd be a GREAT marketing tool. But what do I know.

 

[Gavin]

It'd be nice if Nissan gave a closer delivery date to those who will be charging from PV. Seems it'd be a GREAT marketing tool. But what do I know.

I'd be fine with that, my panels go up 1st week of July.

As for the slope and such...yeah, I was wrong....4 inch off set from roof, no extra angle...helps keep it safer in winds...

Gavin

 

[garygid]

When you first see the Utility Service Meter spin (fast) backward ...
you get one additional "joy" to count in your life!

 

[mitch672]

When you first see the Utility Service Meter spin (fast) backward ...
you get one additional "joy" to count in your life!

mine will never "spin backwards" 1600KW month usage, 5KW PV array will only supply at most 1/4 to 1/3 of that.