Blog Archives

September 7, 2011 | 3 comments so far

Itek Energy Solar Modules Hit the Market

They are finally here, an affordable solution for solar power systems in Washington state that can still take full advantage of the Washington production incentives. Itek Energy, a Bellingham based solar module manufacturer is now producing high quality 240W panels that qualify for Washington’s enhanced production incentive. With made in Washington modules and inverters customers qualify to receive $0.54/kwh for the energy they produce up to a maximum of $5000 of income per year until 2020. That is a potential $40,000 of income.

Average system costs with the Itek Energy modules and string inverters range from $6.75-$7.50/W based on system size and difficulty of installation. An average 4kW home system would range in price from $27,000 to $30,000. With the Washington production incentive and 30% federal tax credit systems can usually pay back with 10 years.

There has never been a better time to consider an investment in solar energy in the Evergreen State. Every month that passes by is another month of production incentives being missed out upon.

Contact us now for more information.

Posted in Commerical Solar, Pacific Northwest Solar, Residential Solar, Washington Solar | Tags: , , , , , ,

August 17, 2011 | 1 comment so far

NE Portland Residential Solar

This NE Portland residential solar array was installed on August 11, 2010. The customer was successfully enrolled in the Solar Payment Option Pilot program through Pacific Power. Since the customer will be receiving production based payments for the 15 year contract period it was essential to maximize the solar potential of the roof space.

We were able to install a total of 26 Solarworld 240W modules on the roof for a 6.24kW array. Each solar module was connected to an Enphase M190 micro inverter. This allowed us to monitor the production of each individual module and see exactly how the system produces over a full year.

Solar Production Estimates

In order to estimate solar production we refer to the Energy Trust of Oregon standards. The array was South facing at 180 degrees and had an average tilt of about 20 degrees.  Shading was minimal and is estimated to be about 1% annually.

In order to calculate the yearly production estimate we multiply the array size (6.24kW) by the shading factor (99%), the tilt and orientation factor (estimated at 96% from Energy Trust Website) and (1.08 kwh/Watt DC per year). This last factor is based on local production capacity and varies by region.

Total Yearly Production Estimate= 6240 *0.99*0.96*1.08=6405 kwh/year

Real Solar Production Data

After exactly one full year we are pleased to report that the system beat the initial expectations and produced 6870 kwh. The 465kwh of extra production equate to extra money earned in the Solar Payment Option program.

465 kwh* $0.65/kwh=$302 per year

Also, we can now calculate the correct local production capacity number. We initially used 1.08 for Portland, OR.

(6870 kwh/year)/(6240 watts*0.99*0.98)=1.16

I can attribute a large part of this increased production to the Enphase Micro inverters.

Final Thoughts

One of the greatest aspects of solar energy is its predictability. With over 100 years of local weather data in most areas we can very accurately predict how much solar energy will be produced on a monthly and yearly basis. Since installing solar modules on a business or residence is often a significant investment it is comforting to know that your investment is predictable and reliable.



Posted in Oregon Feed-in tariff, Pacific Northwest Solar, Project Profiles, Residential Solar, Solar 101, solar install oregon, solar panels, solar panels portland, solar power oregon, Solar Technology | Tags: , , , , , , , , , , ,

May 3, 2011 | 6 comments so far

How much energy will my solar array produce and what will that do to my electric bill?

This is one of the most common questions that we hear and often times there are misconceptions about just how much energy your residential solar system will produce. A good place to start for any home or business owner is with your electric bill from your utility provider. In most cases there is a bar graph that shows your yearly electric usage in units of  kilowatt-hrs(kwh)/day.

In January, for example, this home used on average 144 kwh/day. Multiplying this number by 31 days and we can calculate that 4464 kwh were used in the month of January. Going month by month and adding up all of the kwh usage, you can calculate the usage for the entire year. For this particular graph the yearly usage is about 36,840 kwh.

What exactly is a kwh you may ask?

Think of a standard 60W incandescent light bulb. 60W is the power requirement for this bulb. If you leave this light bulb on for one hour this bulb has used 60 watt-hours of energy. If the light is on for 10 hours the bulb has used 600 watt-hours of energy. Dividing watt-hours by one thousand gives you kilowatt-hours. So, leaving a 60W light bulb on for ten hours uses 0.6 kwh of electricity.

How many kwh will my solar energy system produce?

Now that we know how to determine our yearly kwh usage from one electric bill statement, the next step is to understand how many kwh a solar electric system will produce. Solar energy system production is based on many factors including system size, shading, roof pitch, and roof orientation. The ideal roof pitch and orientation for a system in Portland, OR is 32 degrees at 190 degrees.

As a general rule of thumb, you can assume that for every 1kW of solar energy your system in Portland will produce 1000 kwh/year of electricity.

For example, if you install a 3kW solar electric system it will produce approximately 3000 kwh/year of electricity. If you calculate from your electric bill that your yearly usage is 10000kwh then you know your system will offset 30% of your yearly bill.





Posted in FAQ's, Residential Solar, Solar 101 | Tags: , ,