Iceland’s Renewable Wealth, from Hot Rocks to Cold Desert
October 8, 2013
The Hellisheiði Power Station is the largest geothermal power station in the world. It was just one of the stops we made today in a quick trip across a small country. Southern Iceland is a great place for a primer on the pluses and minuses of renewable energy, in a country that already produces essentially all of its electricity from renewable sources.
At 300 megawatts, the Hellisheiði installation produces a significant fraction of Iceland’s power. While the plant is very clean, it is not a perfect system. There are emissions of sulphur which acidify local waters, and corrode equipment in nearby areas. The impact on water supplies is minimal, but measurable. The local area has a detectable sulphurous odor – something I’ve gotten used to, as it is readily detectable any time you take a shower or use hot water in Reykjavik. Attempts to re-inject contaminated water into the earth have been blamed for small tremors in the local area, so for the moment, there is no solution to the more-annoying-than-dangerous effluent.
Geothermal heat is a resource that is not infinite. A given site can eventually be tapped out. Carefully managed, the location is expected to continue to produce power for centuries to come.
Further inland, across flat plains of Iceland’s best agricultural zone, one passes hundreds of grazing sheep and the unique Icelandic horses, that we can see already are beginning to show shaggy winter coats.
The fertile volcanic soils gradually give way to a rocky cold desert, sliced by rivers flowing off spring fed lakes and melting glaciers further east. Here we took a look at the other terms in Iceland’s renewable equation – hydroelectric, the biggest contributor for now, and the new player, wind turbines.
The Burfell Hydroelectric station, 270 megawatts in capacity, is part of a series of 6 stations which produce in total about a gigawatt of power. Hydro is the workhorse of Iceland’s electrical output, most of which goes to supplying power to multinational ore processing facilities, some very large, which can be seen in the area surrounding the capital. Nearby, a pair of 1 MW wind turbines are running as part of a project to demonstrate whether wind and hydro can make a well matched pair. Wind here tends to blow hardest in winter, while the hydro resource is greatest in summer. The two compliment each other well, as hydro, even in the off season, can be readily matched to strong-but-variable wind, to keep power supplies steady.
One of the two turbines has heating elements to dampen icing on the blades, the other has no such heating – an attempt to observe the difference in icing impact on safety and power production. As luck would have it, warmer weather since the turbines were installed in the last year has made ice buildup rare so far.
The takeaway – there are no free lunches. But some of them are a lot cheaper and more nutritious than others.
For now, Iceland’s total production is relatively small, on the order of a few gigawatts total. There is talk of an undersea cable connecting to Scotland, and the wider European grid, so far not seen as economic. Yet, Iceland’s wind resource may be immense, and it already produces more than enough hydro and geothermal power for its small population. One proposed way forward is using cheap renewables to split seawater into hydrogen, to supply a global H2 economy, but that is some way off, if it ever develops at all.
Each nation has its own set of resources and obstacles – the engineering challenge is to best manage those resources to create needed power and still meet the goal of decarbonizing over coming decades. Iceland is an important laboratory where useful experience will be gained on the way to a renewably powered planet.