The RenSMART Solar PV Estimation Process

1. Energy Arriving from the Sun

• Given your location, we look up the average amount of solar energy arriving from the PVGIS solar atlas. You can take a look at it here
• We then calculate the distribution of this energy over an average year. This distribution is taken from the NASA POWER projects database of world renewable energy resources You can take a look at it

2. Conversion to Electrical Energy

• We use an average efficiency rating for solar panel energy conversion of 14%. Panels are available for sale in the uk with efficiency of between 6% and 18%
• We have a list of most panel models and their specifications available here . You can set a different efficiency value by pressing the Show Advanced Fields button under the Solar PV tab
• We multiply the available roof area by the solar energy arriving and the efficiency
• We then apply factors to calculate the effect of roof pitch, roof orientation and shading
• Finally we apply a reduction factor to allow for inverter and cable losses that occur when the solar panels direct current is converted into an alternating current suitable for use in a property or for exporting to the grid.
• We calculate this value for each month of the year.

3. Calculating Guide Price

• We have analysed a number of solar pv installation quotes provided and developed a price calculation that you can review here . This is the calculation we use to give a guide price based on the peak output of the chosen panels.

3. Estimated Financial Projection

• Using the locations energy use and the chosen energy use profile, we match the solar pv installations output with the energy used.
• Any energy that is not used on site, we mark as exported.
• We display this under the Energy Projection tab
• Using the given import(buy) tariff, and export(sell) tariff and the clean energy cashback feed-in tariff for a system of the chosen size, we calculate an estimated value for each year.