Between 1 pm and 2 pm on Friday, June 6, Germany’s solar photovoltaic systems generated a record 24.24 GW. The real peak came three days later, when they provided 50.6% of the nation’s electricity, which shows solar technology’s potential. The current reality is that solar contributed only 6% of the nation’s electricity during the first five months of 2014, but this will change. The key to Germany’s solar potential is energy storage.
On A Residential Level
Instead of relying on the grid, some solar users store energy and only feed the excess to the grid, then only draw upon the grid when their batteries are depleted.
Close to 7,000 of these battery systems were installed in 2013.
Tobias Rothacher, renewable energies expert at Germany Trade & Invest, expects to see more. Battery sales will increase as their price falls, and once battery parity is achieved, possibly “within the next two years,” the majority of PV sales will probably be in conjunction with battery.
He explained, “Since the cost of electricity from PV is significantly lower than buying energy from the grid (~EUR 0.15 PV vs. ~EUR 0.30 utility), customers want to use as high a proportion of electricity from their PV systems as possible. If they were to feed the electricity into the grid, they would only receive a feed-in tariff of around EUR 0.13 – meaning that self-used energy from PV is worth twice as much as energy fed into the grid.
Rooftop solar solars with “PV-only” systems only obtain around 30-35% of their energy from solar, and their excess electricity ends up on the grid.
Add a battery system to this equation, and these same systems can obtain twice as much electricity (60-70%) for a household’s annual consumption.
“From now on, every new solar system that is installed in Germany increases the need for electricity storage solutions,” Rothacher said. “The cost of storage systems is forecast to drop in the coming years and this means that storage is not only becoming more necessary – it is becoming more attractive from a financial point of view as well.”
He added that, “several small-scale PV storage system manufacturers are working on bundling their battery systems in order to provide grid services (e.g. balancing power). One example is Econamic Grid (in Germany only).”
On A National Level
As for large-scale energy storage, the government introduced a 200 million euro funding program to support storage projects based on various technologies in 2011. Since then, many such large-scale storage projects have been realized and are being operated in order to gain experience and validate the technologies.
On sunny days, more than 1.4 million German PV systems are currently feeding surplus energy to the grid, but this number will increase.
Though the installation rate has decreased, no systems are expected to go offline until 2025, which is when the nation’s first solar panels reach retirement age. Every solar installation up that point will increase Germany’s overall output.
“The direct self-consumption potential for PV energy is around 74 TWh p.a. which would require an installed PV capacity of around 100 GWp,” Rothacher said.” Only with storage could the PV market grow further (taken together, all PV-suitable rooftops and facades in Germany could potentially provide an installed capacity of around 200 GWp).”
He stressed that Germany’s solar potential was demonstrated during the first two weeks of June.
“From now on, every new solar system that is installed in Germany increases the need for electricity storage solutions.”