Are energy storage islands the green solution we need?
Denmark is a windy place. Windy enough to provide 20 percent of the country’s power generation from both onshore and offshore wind farms. As growth in wind power continues, the problem of large-scale energy storage from wind becomes an increasing challenge.
With a focus on the abundant wind energy in Denmark and an understanding of the challenge, Copenhagen-based architectural firm Gottlieb Paludan has proposed an innovative design for energy storage called Green Power Island.
While the design for Green Power Island is new, the fundamental concept behind it isn’t, using pumped hydro to store renewable energy – an idea already in wide use. Conventional pumped hydro systems use vertically separated reservoirs to utilize the power of water and gravity. During low demand water is pumped using excess energy from the lower to the upper reservoir. As demand increases, the water is allowed to flow downhill into the lower reservoir, generating electricity in the process.
The system is limited by the amount of water that can be stored and the height difference between the two reservoirs. Gottlieb Paludan takes the idea and gives it a unique “Danish twist.” Green Power Island proposes using seawater pumped into a lagoon-like reservoir built into an artificial island. When demand is low, pumps driven by wind turbines empties the reservoir. At peak periods, water is allowed to flow back into the reservoir, through turbines generating electricity to meet the rising demand.
With plans already drawn for several locales, including Copenhagen, Bahrain, Jiangsu, and Tampa, Florida, each island is designed to enhance the surrounding environment and utilize the space with mixed used capabilities. Built primarily around storage of wind energy, the islands can also include PV and concentrated solar, and even biomass production. Many islands also have plans for recreation trails, beaches, harbors, even residential and business units.
How green is that island?
Are there substantial engineering and environmental concerns with the Green Power Island concept? As one ex-governor might say, you betcha. Issues that Sten Sedring, communications officer for Gottlieb Paludan, readily acknowledges. Concerns of the impact on the seabed and surrounding habitat chief among them. Nonetheless, it does provide a means of utility scale renewable energy production and storage near demand centers (no need for long distance transmission lines), and Sedring argues that with mixed-used planning as a key feature, Green Power Islands could enhance their surroundings in a variety of ways beyond just power production.
It beats climate negotiations (business as usual)…
I first learned of Green Power Island last December while playing hooky for a day from the COP15 climate conference in Copenhagen. Given the choice of spending another day watching the bitter, log-jammed negotiations unfold at the Bella Center, I opted instead of joining a small band of journalists for a press trip highlighting Danish innovation. It was a refreshing change of pace.
There are no doubt significant hurdles to overcome before Green Power Island could ever become reality. Some might say that even if it were possible, it would be little more than a huge manmade offshore monstrosity. To those I would suggest, consider the options. We are digging deep into the ocean’s depths, wringing tar from sand, blowing the tops off of mountains – all for one more drop of oil, one more lump of coal. To most of us, this environmental destruction is largely out of sight, out of mind. That is, until disaster strikes, as surely it does, and surely it will.
We find ourselves at a time when we desperately need solutions, business as usual won’t cut it anymore. If there is one certainty, it is that the world we live in will look very different 50 years from now than it does now – one way or another.
Whether Green Power Island becomes a viable solution or not, it is at least an idea, a sincere attempt at a solution and a vision for how our world might look in future. It could be worse.