When deciding if solar panels are the right investment for your home, there is much more than simply the savings to the environment to take into consideration. While we would all love to invest money out of the goodness of our hearts, most people admit that making savings or even income from their solar PV investment is the ultimate goal.
The government has offered very generous feed-in-tariffs for solar panel installations over the last two years, however these have fallen significantly in recent months and will continue to do so as the cost of panels and installation becomes less. So before you make that all important decision to invest in solar panels you need to know what the return will be and whether it is a sound investment.
While there are a number of online calculators available, it is important to remember that they cannot take into account the amount of sunlight your panels are exposed to and the effect of tree growth, or the amount of cloud cover. So use these calculators as a guide only.
Calculating your return
How energy efficient is your home?
Before installation you will need to ensure that your home meets a minimum energy efficiency level. This is measured via an Energy Performance Certificate. Your level of tariff will be judged on what band you fall into.
- Band D and above: 15p/kWh
- Band E and below: 9p/kWh
A typical UK roof slope will be around 40 degrees and will be based on the slope of the side of your roof which faces the sun. You may need to estimate this aspect, but it can range from 0 degrees (a flat roof) to 180 degrees (a wall).
Which direction does your roof face? If it faces directly south, you can expect that you will get sun on your panels for most of the day and better results.
The system size
How many panels are you wanting to purchase and what will the total output be in kilowatts. Once again you may have to estimate this. Most homes will have around 6-15 panels.
How much the solar panels will be costing (if known)
The calculator will take all of this information and give you an estimation of what income you can get from your investment. This will also indicate how much you can expect to make over the 25 year investment period. Based on an average sized home which faces south, the return will be around £400 per year or around one third of the total electricity expenditure.