Photo credit: Benny Wielandt.

By Benny Wielandt

Iceland is the first country in the world to create an economy generated through industries being run by renewable energy. There are still large amounts of untapped energy in Iceland.

The country has unique geology, allowing it to produce renewable energy cheaply from a number of sources. It is located on the Mid-Atlantic Ridge, one of the most tectonically active places in the world. Iceland has over 200 volcanoes and over 600 hot springs.

Iceland lies over a rift between two continental plates, the North-American and the European plates. There are over 20 high-temperature steam fields that are at least 150 °C [300°F]; many of them reach temperatures of 250 °C. This allows Iceland to harness geothermal energy, and these steam fields are used for heating everything from houses to swimming pools.

Geothermal power For hundreds of years, the Icelandic people used their hot springs for bathing and washing clothes. The first use of geothermal energy for space heating did not come until 1907 when a farmer ran a pipe from a hot spring to lead steam into his house. In 1930, the first pipeline was constructed in Reykjavik and was used to heat two schools, 60 homes, and the main hospital. It was a 3 km pipeline running from one of the hot springs outside the city. In 1943 the first district heating company started with geothermal power. An 18 km (11 miles) pipeline ran through the city of Reykjavík, and by 1945 it was connected to over 3000 homes.

Five major geothermal power plants exist in Iceland, producing approximately 27 % of the nation’s electricity. The rest of the electricity is produced by hydropower, with just 0,1 % produced by carbon-based fuels.

In 2016 geothermal energy provided about 65% of primary energy, the share of hydropower was 20%, and the share of fossil fuels (mainly fuels for the transport sector) was 15%. The main use of geothermal energy is for space heating, distributed to buildings through extensive district-heating systems. About 85% of all houses in Iceland are heated with geothermal energy.

In 2015, the total electricity consumption in Iceland was 18,798 Gigawatt hours (GWh). Renewable energy provided almost 100% of electricity production.

The potential for growth in Icelandic geothermal energy is great. One possibility is even to build underwater transmission cables connecting Iceland to the UK, 700 miles away, and send the extra power there.

Iceland’s power companies also see a future in bringing large energy consumers directly to the power source. The country has already attracted a number of data centres, whose servers require huge amounts of energy without the risk of an electrical outage.

Hydropower

Hydropower is harnessed from glacial rivers and waterfalls. Most of the hydropower plants are owned by Landsvirkjun (the National Power Company). Iceland is the world’s largest green energy producer and largest electricity producer per capita, with approx. 55,000 kWh per person per year. In comparison, the EU average is less than 6,000 kWh.

It is estimated that Iceland generates only 17% of the harnessable hydroelectric energy in the country. The government believes another 30 Terawatt hours (TWh) of hydropower could be produced each year. This is in spite of the sources to remain unharnessed for environmental reasons.

The first hydropower plant was built in 1904 by a local developer. It was located just outside Reykjavik and produced 9 kW of power. The first municipal hydropower plant was built in 1921, and it could produce 1 MW of power. This plant alone quadrupled the amount of electricity in the country.

In the 1950s two hydropower plants were built on the Sog River, one in 1953 which produced 31 MW, and the other in 1959 which produced 26.4 MW.

These two plants were the first to be built mainly for industrial purposes and were co-owned by the State. The process continued in 1965 when the national power company, Landsvirkjun, was founded. It was owned by the Icelandic government and the municipality of Reykjavik. In 1969, they built a 210 megawatt (MW) plant to supply the southeast with electricity and also to run an aluminium smelting plant that could produce 33,000 tons of aluminium a year.

In 2009 Iceland built its biggest hydropower project to date, the Kárahnjúkar Hydropower Plant, a 690 MW hydroelectric plant to provide energy for another aluminium smelter. However, this project was strongly opposed by environmentalists.

Bathing

After space heating, and electricity generation, the heating of swimming pools is another important use of geothermal energy. There are about 169 recreational swimming centres operating in Iceland, 138 of which use geothermal heat. Based on the surface area, 90% of the pools are heated by geothermal sources, 8% by electricity, and 2% by burning oil and waste.

Of the geothermally heated pools, about 108 are public and about 30 are pools located in schools and other institutions. Most of the public pools are open-air pools used throughout the year. The pools serve recreational purposes and are also used for schools compulsory swimming lessons. Swimming is very popular in Iceland and pool attendance has increased in recent years. In the Reykjavik area alone there are 17 public swimming pools.

Iceland Deep Drilling Project

At Iceland Deep Drilling Project (IDDP) near Reykjavik, scientists and engineers are pursuing another energy source of the future. To unlock the energy, they have drilled down toward the centre of the Earth, through layers of soil and rock, stopping just short of a chamber of molten magma more than 4700 m below the surface. Temperatures hit 427°C at that depth, making water so hot that it takes a “supercritical” form at high pressure, a physical state neither solid, liquid or gas.

The team is now pumping cold water into the hole to expand it to a size suitable to run a power plant. If everything goes well, the IDDP site could be operable in a few years, although a precise timeline is difficult due to the pioneering nature of the project.

IDDP’s most significant implication may well be the knowledge that emerges from the project. Geothermal energy provided less than 1% of the world’s electricity in 2014. The International Renewable Energy Agency (IRENA) says that this number should grow fivefold by 2030.

Iceland as a geothermal pioneer

Iceland has been building its reputation as a clean energy innovator for years. Like most nations pursuing rapid development, Iceland relied on coal in the years following WWII.

The switch to clean energy was an economic decision. The rivers and lakes and waterfalls offered an easy way to generate power to replace imported carbon-based fuels. Still, building more power plants in the 1970s and ’80s made little sense to the leaders in a country with a lot of hydropower but with a small population. Iceland had large energy resources but very little industry to use them.

Therefore, in the following decades, a number of Icelandic business and government leaders campaigned to attract new industries that could utilize all that power that would otherwise be wasted. Their message was clear: Iceland electricity is cheap and Iceland will almost never have a blackout. Companies moved in, and between 1990 and 2014, Iceland’s geothermal electricity production increased 1,700%, while the population grew only 25%.

Hydrogen or electrical?

The relatively small scale of the infrastructure of Iceland would ease a transition from oil to hydrogen, and the abundant natural energy could be harnessed to produce hydrogen.

The country’s first hydrogen station opened in 2003 in Reykjavik. To avoid transmission difficulties, hydrogen is produced on-site with electrolysis . Energy used to produce the hydrogen comes from Iceland’s renewable resources. And the energy cycle, from water to the hydrogen in the fuel cells, emits no CO2.

But this abundance of renewables also makes Iceland an obvious market for electric vehicles. And as electric vehicles are less expensive than hydrogen vehicles and many times more efficient, the country may switch to electric vehicles. Iceland’s 1 359 km (840 miles) Ring Road route circling the country could be covered by 14 fast-charging stations.

A greenhouse heated by geothermal energy. Photo credit: Benny Wielandt.

Greenhouses

Another important use of geothermal energy is for heating greenhouses. This use began in Iceland in 1924. The majority of Iceland’s greenhouses are located in the southwest, and most are enclosed in glass. It is common to use inert growing media (volcanic scoria, rhyolite) on concrete floors with individual plant watering. Geothermal steam is used to boil and disinfect the soil. The increasing use of electric lighting in recent years has extended the growing season. Some greenhouses now have artificial lighting 18 hours a day all year round. CO2 enrichment in greenhouses is also common, mainly though CO2 produced in the geothermal plant at Hædarendi.

50% of greenhouse area is used for growing vegetables and strawberries, 26% for cut flowers and pot plants and 24% are for nurseries for bedding- and forest plants. The total surface area of greenhouses has actually decreased, despite an increase in total production. This is due to increased use of artificial lighting and of CO2 in the greenhouse sector.

Benny Wielandt, Copenhagen, is a Senior Lecturer in Green Plumbing and Heating (retired).