Solar is a primary source of carbon-neutral electricity but it is simply not available after sundown when the demand for energy peaks. Operators of photovoltaic (PV) plants are starting to compensate for the intermittent nature of solar energy by building plants that combine photovoltaic capacity with battery banks.
On August 1st an innovative project in Großschirma, Saxony was unveiled by the Leipzig based project developer Green Energy 3000. The plant combines 5.1 MW of photovoltaic capacity bolstered by 1.7 MW of battery storage. Electricity is temporarily held, then fed into the grid subject to demand, balancing out fluctuations.
"This marks the start of a new era” says Andreas Renker, CEO of Green Energy 3000, in an article in . “The commercial use of battery storage systems in combination with electricity from renewables will ensure a cheap, secure power supply in the long term.”
The project will be orchestrated under a ten year Power Purchase Agreement (PPA) between Green Energy 3000 and EDF subsidiaries EDF Trading and E2M. A PPA allows renewables projects to increase their level of revenue certainty, as the buyer commits to a 10 – 20 year fixed price. The buyer gains ‘green attributes’ such as Renewable Energy Certificates and the PPA gives confidence to project financiers.
Imke Janssen from EDF Trading comments: "Such projects only work if we stand together. Our role is long-term power purchasing from this combination system at a fixed rate, assuming price and volume risks that could result from fluctuating solar radiation and system availability."
Hybrid plants with large-scale storage eliminate the need to fill the supply gap from conventional sources, lowering actual and environmental costs. Green Energy 3000 is planning several further sites based on the Saxony model.