|June 8: Utsira's energy independence
Fifty years after the Norwegian island Utsira was first connected to the grid, it has become the demosite for energy indepedence. Two windturbines and a hydrogen storage power the island.
Reidar Klovninh, a retired sea captain, takes us down the Hydrogen Road at the tiny island of Utsira, a rocky outcrop 18 kilometres off the Norwegian coast. Reidar is one of the 215 inhabitants of the island. “Today it's dead calm”, he says. Normally, as records from the lighthouse show, there is a strong wind blowing over the island.
The Hydrogen Road leads to an experimental set-up that StatoilHydro has built here to gain experience with power self-sufficiency. Two Enercon 600 kilowatt windturbines have been placed on the east side of the island. At the base of one of them, a collection of white sheds houses a hydrogen facility that is to buffer excess wind power and to provide power on the days when there is no wind. While the island has about hundred households, only ten of them are connected to the hydrogen system. The rest relies, as before, on electricity from the grid when there is not enough wind (10 to 20 percent of the time).
The hydrogen facility consists of an hydrolysis unit to produce hydrogen from electricity, a compressor (200 bar), storage tanks, a gas-engine coupled to a generator (60 kw) and a fuel cell unit (10 kw). The system has been in operation since 2005.
The ten households connected to the hydrogen unit have been off-grid for 60 percent of the time, says project manager Torgeir Nakken. The system has been switched off for 40 percent of the time for both planned maintenance and unexpected failures.
At the moment of our visit, the gas-engine had to be replaced. This is the main producer of power from hydrogen which until now has been in succesful operation.
The fuelcells have been a constant cause of problems, according to Nakken. They had problems when functioning, and in rest they tended to dry out.
Although in theory fuel cells are better at converting hydrogen into power (overall efficiency 40 percent), the less efficient gas-engine (25 percent) proved to be more reliable in practice.
“You must remember, efficiency is not the main issue here”, says Nakken. “Power is plentiful with the two turbines. We even pitched one of the turbines down to 150 kw because it was producing too much for our ten households.”
The main challenge according to Nakken was to provide a constant and good quality power to the ten houses on the hydrogen system, despite the inherent fluctuations in wind power. “There were some flickerings in the beginning, but we managed to produce a good quality power now. ”One of the means by which they managed to to do so was to include a flywheel in the set-up. This helped to flatten out power fluctations due to changing winds.
There is no end-date for the experiment. StatoilHydro is looking for means to reduce the costs for the system and develop it into a solution for power self-sufficieny for remote places.
Reidar Klovninh tells us there are plans for four additional wind turbines just off the island, but that would only be feasible if the current connection to the grid on the mainland will be upgraded. The current cable dates from 1958 – a blessing for the inhabitants who until then relied mainly on peat for warming their houses – and has a maximal capacity of 1 megawatt.
A more powerful cable to the mainland would also open the possibility for a planned offshore park with 50 turbines to the west of the island. Considering the depth there (200 meters), floating windturbines would be the only option.
The first one of those, the HyWind, is just visible on the southern horizon where it has been moored 10 kilometres off the southern tip of Karmøy for a two year test period.
In the latter option, Utsira with its favourable wind would become a hub in deep water offshore power production.
External link: StatoilHydro page on Utsira