Hellisheiði power plant Geothermal power plants harness green renewable energy, but they nevertheless leave a significant environmental footprint: Boreholes, roads and transmission pipes all take space and destroy untouched nature. Photo/Valli
The Geothermal power utility Orka Náttúrunnar, which operates among other things the Hellisheiði power plant has found a way to make it's power even greener. By reclaiming original vegetation around their power plant the plant ensures that the environmental impact is minimal.
Geothermal power leaves an environmental footprint
Even if geothermal power is green and a renewable energy source, its harnessing requires drilling boreholes, laying roads, building power plants and laying pipes to deliver the steam from the boreholes to the power plant. In the process the operation causes significant disruption and destruction to the original landscape and vegetation.
Read more: New borehole on Reykjanes peninsula promises to revolutionize geothermal power
In places like the lava fields of Hellisheiði heath the native vegetation and moss mats are fragile and take decades to recover, which means that harnessing the green energy potentially leaves ugly black and gray wounds.
Orka Náttúrunnar, which is owned by Reykjavík and other metropolitan municipalities, operates this third largest geothermal power plant in the world, has been working actively to solve this problem.
Lava boulders and vegetation is stored to be re-used
The first step for the utility is to remove all vegetation at construction sites. The moss mat or the topsoil, with the plants and their root systems, are removed and stored to be re-introduced to the site. The utility operates industrial freezers to store moss for longer periods, up to two years. Lava boulders are also stored so that the landscape can be reconstructed.
Magnea Magnúsdóttir, who is in charge of vegetation reclamation for the utility, told the local newspaper Fréttablaðið that the moss has been frozen for up to two years, before being thawed and re-planted. "It has worked better than we could have hoped. The moss came out of the freezer beautiful and green."
Read more: Nine fascinating facts about geothermal energy and Reykjavík
This moss was then used to cover lava boulders which were returned to an area around a steam pipeline connecting boreholes to the main power plant (see photo below).
The utility has also been working hard to reclaim original vegetation at older sites which had been disturbed and never repaired. All moss which the utility removes is therefore stored to be re-used somewhere.
Best practices being adopted by others in Iceland
The utility has also experimented with "sowing" moss by spreading a porridge of buttermilk and moss leaves which then take root and thus reclaim barren rocks in a couple of years rather than decades.
Since Orka Náttúrunnar introduced its methods of reclaiming original vegetation the state power utility Landsvirkjun has adopted the same methods to reduce the environmental impact of power plants, transmission lines and roads. Now the Icelandic Road and Coastal Administration has adopted similar methods, requiring subcontractors to store and then re-introduce moss they remove when new roads are constructed.
As these pictures show the results can be dramatic!