Total Project Capacity

What is the number?
A total of the installed and in development project capacity kilowatt power (kWp) input per project which is then totaled on the home page. These figures are displayed in U.S. numbers.

How is it calculated?
Total number of installed capacity kWp of all projects.

Data Source
Current Origis Energy solar project portfolio as reflected on the website.

Overall Carbon Emissions Saved Over Coal

What is the number?
It means solar saved the presented number of grams of carbon when compared to coal generation.

How is it calculated?
Using current kWp coupled with http://blueskymodel.org/kilowatt-hour metrics for coal. By comparing to coal we are able to provide a verifiable formula.

Formula
X kWh x the average grams of carbon dioxide per kilowatt-hour produced = Grams of carbon produced

  • 10,000 x 60 = 600,000 (or .6 metric tonnes)
  • 10,000 x 909 = 9,090,000 (or 9.09 metric tonnes)

Data Source
The Origis Energy project installed kWp capacity coupled with Oak Ridge National Labs CO2 emission data for solar and coal via http://blueskymodel.org/kilowatt-hour.

Overall Homes Powered

What is this number?
Number of homes that could be powered by the solar power produced (kWh) by each Origis Energy project which is then totaled on the home page.  This number is based on an average of global home size and electricity use.

How will it be calculated?

The number of homes powered is going to be quite different around the world, based on size and common electrical use.

Background
US home size has fallen a little since the recession, to 201 m2 (2,164 ft2) in 2009. UK house size is relatively small at 76 m2 (818 ft2) while Canadian houses are quite big at 181 m2 (1,948 ft2).  For China the data only reflects urban properties, which now average 60 m2 (646 ft2) and have almost doubled in size in the last 15 years. (source: http://shrinkthatfootprint.com/how-big-is-a-house)

In the US typical household power consumption is about 11,700 kWh each year. In France it is 6,400 kWh, in the UK it is 4,600 kWh and in China around 1,300 kWh.  The global average electricity consumption for households with electricity was roughly 3,500 kWh in 2010. (http://shrinkthatfootprint.com/average-household-electricity-consumption)

There are a very complicating set of factors that would go into calculating an accurate global instead of average number.  Parameters would include efficiency on both the plant and the home end, type of system installed (trackers versus static), how far the power has to travel on the grid and corresponding grid power losses, the house size, the number of occupants, what is being powered, etc.

The Solar Energy Industries Association (SEIA) has calculated a US national average of 164 homes powered per MW of solar produced (source: http://www.seia.org/about/solar-energy/solar-faq/how-many-homes-can-be-powered-1-megawatt-solar-energy)

Solar Power produced (kWh) / 1000 = MWH * 164 = Number of homes powered

i.e. 10,000 kWh / 1000 = 10 * 164 = 1640 homes

Data Source
Current Origis Energy solar portfolio using calculations laid out above.