Microinverters usually cost £100 to £130 more per panel than a string inverter, and the best side-by-side test on an unshaded roof found they produced only about 0.5% more electricity. That test was run in 2011, so Spirit Energy and Gary Does Solar have built a new one on a real UK roof, with 24 LONGi panels split into three independently metered blocks. Over the coming years it will show whether microinverters earn their cost without shade, and whether bifacial panels generate anything extra from the back on an ordinary tiled roof.
