Opinion

Living on the edge

Laid bare: The power optimisers of the SolarEdge system, installed behind each panel, are designed to increase energy output from PV systems by constantly tracking the maximum power point of each module individually
Laid bare: The power optimisers of the SolarEdge system, installed behind each panel, are designed to increase energy output from PV systems by constantly tracking the maximum power point of each module individually
As the first UK renewable energy installer to fit the new SolarEdge PV energy optimisation system, Michael Winstanley of Cheshire-based renewable energy installer The Greener Group gives the lowdown on how it is boosting the output of underperforming PV arrays

Historically, the only solution to an underperforming installation was to fit a new one. But the pioneering new SolarEdge product optimises the output of underperforming systems and can be retrofitted to any existing installation.

The Greener Group has been impressed with the increase in output following the installation of the product, and is keen to inform owners of domestic and commercial installations that if their solar PV system is underperforming, there is now a cost-effective solution.

The Greener Group was recommended to a client who was unhappy with the performance of its solar PV array since its installation in 2011. A site inspection revealed that the installation was spread across the house roof in three different orientations and there was also considerable shading from nearby trees. The Greener Group were aware of a new product by SolarEdge and was confident it was a suitable solution so spoke to its supplier, Dulas MHH (re-branded as BayWa r.e Solar Systems this month), and arranged for the product to be delivered to site the next day.

The installation of the retrofit SolarEdge technology required the temporary removal of the solar panels to allow a power optimiser to be installed behind each panel. The panels and optimisers were connected in series and secured back in place onto the mounting rails. The feature that makes the product unique is the power optimisers that increase the energy output from the PV system by constantly tracking the maximum power point (MPPT) of each module individually. Moreover, the power optimisers monitor the performance of each module and communicate performance data to the SolarEdge monitoring portal for enhanced, cost-effective module-level maintenance.  Each power optimiser is equipped with the unique SafeDC feature which automatically shuts down a module’s DC voltage whenever the inverter of grid power is shut down. The result is that the PV array will operate at its optimum efficiency at all times and ultimately produce more energy per panel.

This new SolarEdge system allows for a traditional installation to be upgraded and benefit from the enhanced features it has to offer. The system is compatible with any inverter and uses a smart bit of kit – the SolarEdge Safety and Monitoring Interface – which works with the power optimisers fitted behind the panels.

We calculated that the installation will generate an additional 400 – 600kW per year: an average increase of 28 per cent. The payback period on the investment is roughly 6 years, and from there, it will generate an additional £200-£250 per annum of additional revenue from the Feed-in Tariff.

Commercial applications
Having successfully installed the SolarEdge Indop technology on a domestic installation, The Greener Group is keen to approach owners of under-performing commercial installations and discuss the potential gains for their business.  During the solar PV rush of 2011 and 2012, systems were often installed in haste without proper design considerations. A commercial system that suffers from shading issues or split orientation could be significantly underperforming and hence not reaching its potential energy yield. Moreover, owners of commercial installations that were put in place as an investment could be earning much less than the projected amount.

For more information, see http://www.thegreenergroup.com