Project Summary

Installing a photovoltaic (PV) system on our home. Our house is 2360 square feet, built in 1999 and has both electric and natural gas utilities. Current electricity use ranges from 900 kWh to 1500 kWh per month, peaking in December… Must be the Christmas lights! The house is situated almost perfectly for solar. Our panels will be on a 33 degree roof that faces almost directly south and with no possible obstructions.

I have been researching Solar PV for our home for number of years and weighing the system costs, available incentives and taxes breaks to what I thought we could afford. With costs at $6.00 to $8.00/watt, I was struggling with REALLY wanting to do this and the practical side of family finances. This last spring I became aware, though my brother, of a Solarize Community project being sponsored by Nike Beaverton, Oregon for employees, friends and family. They had selected a contractor, set a system price of $5/watt and my brother works at Nike… so I couldn’t resist!

System Stats:

Solar System Size: 3.76 kW

2 x Strings of eight SolarWorld 235W panels

1 x 3000KW PV Powered inverter

Portland General Electric (PGE) Net Metering program

Online monitoring module to evaluate solar system output, usage, feed to the grid, etc

Saturday, February 11, 2012

Five Months and Counting

It's been fun and interesting to watch how the system performs through the winter weather and the impact of the winter inclination of the Sun.  Although I was expecting it, I guess I have been little surprised at how low the sun drops on the horizon this time of year in relation to our roof and my neighbor's roof... which throws a shadow on ours.  The power generation on a cool clear sunny January morning will start in the 1400 watts range, then drop during the day to 200-400 watts as the shadow moves across the roof during the day.  Then it pops up again in the afternoon until sundown.  Below, this shot was taken at about 10:00 AM on January 31st and you can see the shadow start to creep onto the panels.

Also as interesting has been to observer when energy is generated on overcast and even rainy days. On your average gray, overcast and drizzly Portland day, I see a couple hundred watts being generated at times.

I have been tracking all the solar generation and overall consumption number for the household and put them into the graph below.  You can see the obvious increase in overall consumption (+ XMAS lights...) and decrease in generation as the days get shorter.  We've yet to have net-zero month of curse, but we remain hope for the coming summer!

Monday, August 29, 2011

Initial Look at Power Production

A number of people have been asking about stats around power production, how it will offset our usage as well as how it compares to our previous usage and bills.  

Some tools are available via the online monitoring of our Inverter which are interesting and I'm studying how to use this data.  Here is a quick example of current status and a weekly production report.  The report only shows what is produced, not what we are using at the household level and whether we're over or under production from our load.  Note though, how the last week has been clear and sunny until today.

I'm also looking forward to additional detailed information that may be provide in our billing from our power provider (PGE).

We are in the final steps of completing inspections and sign-offs, after which time the solar contractor (NW Solar Solutions) will walk through the system with us and provide us with a user's manual.

So, over the next few weeks I hope to be posting more detailed data on power generation and comparisons. 

Please stay tuned!

Thursday, August 25, 2011


The financing, applications and approvals did take some time, but we finally started the installation in the first week of August.  It started with our roof then progressed to rails, panels and final electrical connections.  Pictures are much better than my words, so follow along below.

The components:

SolarWorld 235 PV Panels (16 total!!!)

Advanced Energy PVP3000 Inverter

Solar System Output Production Meter

Roof before Installation:

Old roof removal and stanchion installation:

New roof.....

...and rails to support panels:

Panel Installation:

Inverter and meter installs:

Interesting informational and warning labels everywhere:

And now... we're producing power!!!
Ok, 137 watts, but this was toward the end of the day when the sun was going down.  We have seen it, in the first few days, as high as 3040 watts

A thing of beauty!

Next, tracking our power production....

Thursday, August 11, 2011

Proposals and Paperwork

The Proposals:
Larry with NW Solar Solutions came back with two proposals, one for 3.2 kW and one with 3.7kW.   That being either 2 strings of seven (7) 235 watt PV modules or 2 strings of eight (8) 235 watt PV modules.  At $5/watt plus a $250 Internet monitoring module, the cost
would be either $16,700 or $19,050 respectively.   The choice was easy if I went back to my original statement of , "as big as would fit", we went with the 3.7kW system.

The system would consist of the following basic components:
16 x Solarworld 235 watt PV panels (2 strings of eight)
1 x Advanced Energy PVP3000 PVPowered 3000 watt Inverter
1 x Advanced Energy  PVM1010 Inverter data monitoring module
Various replacement meters and electrical wiring

One thing to note, that I found to be a huge plus, is that both the PV panels and the Inverter are made in Oregon.  So on top of putting Roofers and Electricians to work, the products also provide for Oregon jobs.  Cool.

The Incentives and the Net Cost:
·         ETO Solar Incentive
o    Portland General Electric customers, $1.75/watt (DC) to $20K
o    Paid directly to the Solar contractor
o    $2.10 watt DC, capped at $6,000 ($1500/yr over four years)
·         Federal income tax credit
o    30 percent of net system cost
o    Total installed cost, less the Energy Trust incentive

 In our case, it translated to the following:
Total Value of Installed Photovoltaic System: $19,050.00
Energy Trust of Oregon incentive: $6,580.00
Total Out of Pocket: $12,470.00
Federal Investment Tax Credit: $3,666.00
Oregon RETC 1st year: $1,500.00
Cost of system after first year of Incentives $7,304.00
Oregon RETC years 2-4: $4,500.00
Cost of system after Incentives: $2,804.00

WOW…  $2804 ?!?!?!  I could live with that. The tough part though can be the initial out of pocket, knowing that your state (Oregon) tax credits come to you over four taxes cycles.  But some banks offer special loans just for these types of projects.  Check out Umpqua bank’s Green Street Lending programs, they offer great rates and term.  So we set off to organize our funding.

Another Consideration:
To qualify for ETO incentives, there are a number of requirements.  I mentioned one previously, that the Solar Resource Fraction for the PV location needs to be least 75%.  Another is that your roof must have at least 10 years of life remaining.  If a roof must be replaced after the PV installation, the panels need to be removed and reinstalled and the ETO apparently wants to avoid that for at least 10 years.  Our roof was 12 years old and qualified with more than 10 years of life remaining on it.  But we considered that we wanted to avoid any type of removal and re-installation as long as we could.  So, we got a quote and decided to re-roof only the section of roof that would have the panels installed on them.  This also provides for a better overall installation, because the PV mounting stanchions can be installed while the roof is off and the new roofing installed around them.

Applications and Approvals:
After signing our contract to proceed, we then needed to fill out application for the ETO incentive and the PGE (Portland General Electric) Net Metering program.  Larry had them pre-filled out and explained them to us.  We signed them and he submitted the applications.

A few weeks later we received an acknowledgement, then an acceptance from PGE for the Net Metering program.

The ETO approval took a little longer.  They reviewed the design and requested a modification to the inverter that was specified. Initially a 3500 watt inverter was specified, but apparently due to way the efficiency of the system decreases over it's lifetime and the times of year when full sunlight are not available, they wanted a 3000 watt inverter used instead.   A 3000 Watt inverter will run at full capacity more often... apparently.  So ultimately the ETO application was approved and we were set to go.

Next... the installation!

Saturday, August 6, 2011

Getting Started

In early April my brother linked me up to the sign-up page for the Nike sponsored Solarize Communities project.  I signed up and within a week I was contacted by Larry from Northwest Solar Solutions to come take a look at our house.

The First Visit:
Larry visited few days later and explained the program to me and asked me what I was looking for in PV system?  Answer: As big a Photo Voltaic (PV) system that could fit!  He also brought his electrician with him and we looked over the house. 

The Subs:
As I think is common with most solar contractors, they sub out work to roofing companies and electricians to do the work related to their trades.  The roofers set the mounting stanchions and rails that support the PV panels and the eletricians install the panels and complete all the wiring.  The solar contractor coordinates ALL the paper work, applications and various sub-contractors.

The electrician verified our house electrical could support the installation and Larry looked at our roof to be sure that it would be a good candidate.  Based on house position, roof slope, obstructions and other details, he would calculate our home’s “Solar Resource Fraction” to verify that we qualified for the incentives and credits.  It turned out our Solar Resource Fraction was 90% and we needed to meet at least 75% to qualify for the Energy Trust of Oregon (ETO) Solar Incentive.
What do you think???

So we waited for our proposals……