By combining solar PV and hydrogen fuel cells, what has been described as the world’s first fully off-grid, energy-sufficient housing complex, is in the process of being realized in the Vårgårda Municipality of Sweden.
Started in early 2018, the breakthrough project was initiated by municipal housing company Vårgårda Bostäder, alongside partners Danish firm Better Energy and Sweden-based Nillson Energy.
When complete, all of the apartment complex’s electricity and heating needs –172 flats across six blocks – are expected to be met through on-site solar generation and storage. Indeed, each block is on track to have a PV system installed on its roof, which should cover the energy needs of its residents, while the excess energy will be stored for later use.
A spokesperson for Better Energy told pv magazine that currently one out of a total of six buildings has been built and is in service. “Each building (of 30 flats) has 109 kWp solar on the roof to cover 100% of the electrical and heating needs. So the total when all six building are finished will be 659 kWp,” they said.
Electricity production from hydrogen is a well-known concept, however the Vårgårda project innovated this technique from a residential planning perspective by intertwining it with residential solar systems, thus offering a complementary approach to meeting year-round energy needs in a sustainable fashion.
As such, the harsh Swedish winter climate will be off-set through the long-term hydrogen storage system, thereby maximizing solar surpluses during the long Scandinavian summer days. An additional advantage is that hydrogen electricity generation produces heat as a by-product, offering combined cycle benefits during the harsh winter.
The concept was tested by Nillson Energy in a partnership with AT Solar in May 2018, during the pilot project “RE 8760”.
Commenting, Vice President of Sales for Better Energy, Nicolai Faaborg Andresen, said, “Ironically, our solution involves the limitless energy of the sun and the simplest, lightest, most abundant element on Earth, hydrogen. Resources and technologies right in front of us. We’re just combining them in a new, clean and extremely efficient manner. It’s brilliantly simple.”
Hydrogen can be stored over a long time-span and can be combusted like a fossil fuel; however, one of its main limitations is the large energy input required. Directing solar generation peaks into the hydrogen storage thereby minimizes waste. Hydrogen renewable energy storage solutions, if able to be successfully scaled, thus offer prospects for balancing some of the primary difficulties of solar generation’s relationship with the grid.