Annual income per KW installed.
This is intended to show how effective the system is at generating income. Because the systems are of differing size I have divided the yearly income by the size of the system to allow a fair comparison. It is a mixture of estimated income and actual in each case, so with only limited data it can only really be used as a guide.
Income against installers estimate
Every system has a Micro Generation certificate provided by the installer. This is required to register the system with your power suppliers Micro Generation scheme. This chart shows how well each system is performing compared to how it was originally expected by the installer.
Estimated number of years to Pay back
This is an estimate based on data available so far, how long it will take for the system to pay for itself. It is worth noting that FITs are index linked so increases in rates are likely to decrease the number of years it takes a system to pay for itself. I obviously cannot factor these into my calcualtions so again this is only intended as a rough guide. In conclusion this chart demostrates that purchasers who waited for the price of hardware to reduce before purchasing were rewarded by shorter number of years for system payback, and thus a higher return on investment.