Our Solar Electric Panels: Done!

Yes, it is. New Mexico is one of the best places for solar power.

Found this image showing the difference:

 

Well add me to those putting in a system. Just signed up to put in a 3.04 KW system using 16 x 190w panels. Will not get full efficiency from them, as they will be mounted on the western slope of my roof - not enough roof available that is north facing (those of us down under look north to see the sun). Nearly every company quoting said that this will only result in approx 12% reduction in efficiency.

Nearly all the panels available here in Australia are manufactuered in China. I had one quote from a company that uses SunPower panels, but their quote was almost double that of everyone else. Total cost for me is AU$8,500 after transfer of the RECs (treated as a rebate here in Aust).

Payback period has been estimated as being a mere 4 years because the state government has set a mandate that the electricity providers must pay us a minimum of 60c per KWH, while we only pay 26.2c per KWH, and the rate they pay us cannot reduce until 2017. My supplier is offering 68c per KWH, so the payback is for me is even better. The price is a way that the state government can encourage people to put in PV systems without any rorting of the system - you have to be producing to get the benefit. The government, in turn, subsidises the power providers.

Should get my system installed October.

 

Nice - what panels did you end up getting? It's a fact of life that shipping from China will be a lot cheaper than shipping from the US. How many kWh do you expect to generate/year?

 

My electricity consumption in the past two years is 3256 kwh / year. The electric company allows you to view your consumption, for several years, in fact (Southern California Edison.) I mention this in case others are investigating solar panels.

Since my electric bill is about $30 - 40 per month, and consumption is about 270 kwh / month, I don't know if solar panels make sense. Also my roof has mostly East and West orientation, very little south facing pitches. I assume this means I would get relatively low efficiency.

I can reduce my consumption a bit more by eliminating a spare fridge - it consumes about 1 kwh per day (Kill A Watt meter)

 

Wow, I guess you don't need AC at your location, you must be located very close to the coastline.

Certainly with your monthly bill as low as it is, an investment in solar panels would be more for bragging rights or making a green statement, and not for financial reasons.

I just received my June electric bill, which was $185 for 1,653 kWh consumed. That month is usually the hottest in the summer season, as rain usually makes an appearance in July and August. We were even gone for one week of that time with 2 out of the 3 AC systems turned off.

I am planning to have my 24 panel system mounted on the east-facing side of my home, which is also the rear. This will reduce the visibility of the panels from the front of the house. The bottom 12 panels will be mounted on the solid patio cover and the top 12 panels will be mounted on the roof.

However the panels will be mounted on racks so that they will be facing south (i.e., not flush with the roof.)

I recently bought a Fluke instant read IR thermometer and it turns out that the home thermostats are correctly calibrated. They read 76 degrees, and the thermostat housings are at that temperature +/- one degree.

 

Consider investing in a Solar or Wind Co-op. In the real word, often time investing in PV off site is a better bang for ones buck investing in solar in an ideal location rather than a compromise. For example, right out of the gate a kw of PV in Yakima Washington will yield ~30% more harvest than the same kw in Seattle. Couple that with economy of scal, a large co-op array might make great sense.

Icarus

 

Conservation is always the first step and in general, the least expensive.

With less than 300 kWh/month of electricity usage, you are likely staying within the baseline usage which means that your electricity is cheap - probably around $0.13 / kWh.

With those kinds of rates, it would probably take about 10-15 years to "break even" after tax credits and incentives. It's counterintuitive, but the more electricity you use, the faster a PV system will pay off - if you use a lot and are in the expensive tiers paying $0.30+ / kWh, you can break even in 7 years by building a system that puts you into the lower usage rate.

That said, saving money isn't the only reason to do it - reducing our dependence on fossil fuels and reducing air pollution are others.

If the high initial cost is throwing you off - many companies offer financing plans where they essentially own the system at first and you buy the electricity generated by the system at a reduced rate. I think ideally PACE programs would be better - essentially the cost of the system gets added to your property tax bill.

Having panels face East/West instead of South probably costs about 25% in efficiency - but it depends on the mounting angle. You can run simulations through PVwatts or the CSI calculator.

 

Exactly. I wish one was local. They should be everywhere.

 

I got CEEG panels. CEEG is the largest manufacturer of panels in China so most likely to be around to cover the warrenty offered.

Based on a couple of calculators that I have used, expect approx 3700 KWH per year. We currently use about 9000 KWH per year. A frightening amount when I added it up, but my family are real power wasters - especially when you consider that we use gas for water heating and cooking. Unfortunately I cannot afford a larger system, nor do I have the space to put a larger system in.

 

An update: Installation of this system is scheduled to start on Thursday Sept. 9 and hopefully will be finished by Tuesday of the following week. 9 panels will be mounted on the patio cover and 15 panels will be on the roof. Photos to follow.

My home is located in the 6.0 - 6.5 zone of the map posted by drees, so hopefully the system power output will meet expectations.

 

I bet you're excited! What kind of inverter technology did
you go with?

 

Thanks, John.

Inverter: SMA SB 5000US:
SUNNY BOY 5000US / 6000US / 7000US / 8000US.

PV modules: Schott Poly 225W x 24 modules:
http://www.schottsolar.com/fileadmin/media/us/data_sheets/SCHOTT POLY 220-235 Data Sheet US 0510.pdf

The system will be wired as two 12-module strings in parallel.

 

Every time I see a water feature, I cringe at how much electricity pumping around water purely for show wastes. It's amazing how much electricity it takes to pump water...

Those appear to be very good panels from what I've seen. And they are "local" - they are made in New Mexico.

 

A few photos showing work in progress. Hopefully the job will be done by Wednesday.

 

Yup.

After four days (14 man-days) of work, the system is 98% done. The panels and inverter are producing power.

I also would never monkey with the system until it has passed inspection, but all that is needed is to insert metal bars to short out the solar meter socket, so that current will pass through the socket.

Today the web monitoring device is going to be installed. There's also some touch-up painting and roof tile work to be completed.

Two pairs of #8 wire were used to connect the solar panels to the inverter. #8 wire was also used to connect the inverter to the AC disconnect switch, solar meter and house breaker box. The total run is around 100 feet.

Note the little exhaust pipe in the center of the first photo, for the gas log fireplace. That prevented installation of 3 rows on the roof (original plan was 5 panels x 3 rows on the roof). Instead, 10 panels were installed to the far right of the photo.

The panel angle was set to 29 degrees which is supposed to maximize summer production while complying with Tucson Electric requirements. The weird angles of the panel mounting were required to orient the panels within 20 degrees of south (the porch faces southeast.)

I went through one year's worth of utility invoices. We used ~10,000 kWh over that period. This system is supposed to produce 9,400 kWh annually, so if true that would amount to 94% of our requirements.

As of noon local time today the system was producing 4.5 kW. It is rated at 5.4 kW. I am told that the productivity should peak in October and March, we'll see.

 

Patrick,

Can you post some screen shots of the web management
tool? I'd like to see the granularity that a central inverter's
management tool provides. That is, what level of array
component can you see: individual panel; individual string;
array as a whole; etc.

Because I have Enphase micro-inverters, theirs is the only
web management tool I've actually seen in action.