Samso, a Renewable Energy Island

Fig. 1. Samso. The symbols indicate the main energy production sites. The surrounding box is 28-by-12 kilometres.
Fig. 1. Samso. The symbols indicate the main energy production sites. The surrounding box is 28-by-12 kilometres.

Samso became a 100% renewable energy island in ten years. Eleven wind turbines on land cover the electricity consumption. Renewable energy heating by district heating plants and private installations cover more than 70% of the heating demand. Transportation is still mainly based on fossil fuels, but offshore wind turbines compensate for the transport consumption plus the remaining heating based on fossil fuels.

The island has an electric submarine cable to the mainland Jutland, with electric traffic both ways. We say the island is 100% renewable, but it does not mean the island is autonomous. It refers to the following annual balance:

annual energy consumption = annual renewable energy production

The island still consumes fossil fuel, especially for transportation. The ferries account for about 50 percent of the total transportation energy, and they run on fuel oil. The island went from 13% to 100% during a 10-year project from 1997 to 2007.

Project milestones

Energy plan. The Danish government announces a competition in the spring of 1997. The objective is to appoint a renewable energy island. Five islands participate, and each competitor receives an amount of funding to hire consultancy and write their energy plan. Together with the engineering company Planenergi, the local business association, the municipality, and the farmers' association Samso submits a proposal in June. A committee of external and governmental evaluators review the proposals according to the criteria: use of well tested technology, energy savings, limited requirements for subsidies, local support and initiative, good traffic connections, and enough tourism for the project to be a display window for renewable energy. The minister for the environment and energy, Svend Auken, grants Samso the title Denmark's Renewable Energy Island in November.

Samso Energy and Environmental Office. The organization Samso Energy and Environmental Office (SEMK) is formed in July in order to have an information office for the public. The Danish Energy Authority decides to support SEMK, and in Feb 1998 it is possible to open a professional office with an energy consultant: Søren Hermansen. The governmental funding lasts until 2002 after a new government goes into power, and the SEMK funding is thereafter based on projects and consulting.

Electric cars. The Samso municipality leases four Citroen Berlingo electric vehicles for the municipal home care as a supplement to three petrol driven cars. Unfortunately the project is abandoned three years later for various reasons: 1) the batteries needed service on the mainland, and often one car was missing, and 2) the 12 social workers that drove the cars applied less than optimal driving techniques, as they were often in a hurry to attend to emergency calls. The fuel consumption was equivalent to 1.40 DKK/km (0.19 EUR/km). Later in 2006 the Energy Academy receives a Citroen Saxo from the Arhus municipality, and it runs as expected.

Heating campaign. The energy organizations implement two campaigns starting in 1999. The topics are renewable energy and energy savings directed toward 850 houses and 750 summer cottages or temporary residences. Two energy consultants visited 74 families, and about 1/4 establish solar heating after the visit.

Wind turbines. Eleven land based wind turbines start to operate, the size of each is 1 megawatt. Many citizens own two of the wind turbines in a co-operative after forming a guild, and nine farmers own one wind turbine each. The total production of the 11 turbines is more or less equivalent to the electricity demand on the island. The government guarantees a minimal selling price at 0.60 DKK/kWh (0.08 EUR/kWh) for the first 12 000 MWh, corresponding to about 5 years of operation, and thereafter 0.43 DKK/kWh (0.057 EUR/kWh) until the end of the tenth year. Thereafter the selling price equals the market price governed by the electricity exchange NordPool.

District Heating Plant, Nordby-Maarup(external link). A very active action group of citizens manage to collect more than 70% of the potential consumers, and the district heating plant goes into operation years ahead of schedule. Due to the relatively large amount of summer residents and the company Br. Kjeldahl's need for process heat to dry onions, an array of solar collectors is built into the plant. The energy supplier NRGi owns the plant.

Onsbjerg district heating plant. A straw fired heating plant starts to supply heating to 75 consumers in Onsbjerg. The company Kremmer Jensen Varmeforsyning Aps owns the plant, controlled by two local brothers. During the intial phases of the project, the initial location was rejected by citizens and the church, but they agree on a better location also in agreement with the local branch of the national environmental organization (the Danish Society for Nature Conservation).

Canola oil. The local wind turbine trust buy and establish together with three organic farmers a rapeseed oil press. The plant oil is for transportation and the remaining cake is fotter for the cows. The first tractor runs on canola oil in 2003. Later on in 2008 three oil presses are in operation.

Fig. 2. Renewable energy percentage. When the offshore wind turbines went into operation in 2003, the renewable energy percentage went to 100.

Offshore wind turbines. Ten wind turbines in the sea south of Samso start operating. Each turbine is 2.3 megawatt and reach 103 metres up from sea level to the upper tip of the wings, and they are a large boost to the renewable energy production (Fig. 2). The cost of each wind turbine is 25 mill DKK (3.3 mill EUR). The Samso municipality borrowed 125 mill DKK (17 mill EUR) and bought five wind turbines. This way each citizen is said to own a piece of a wind turbine at the value of 30 000 DKK (4 000 EUR). A possible municipal profit may only be invested in new energy projects; it can not be spent on the ordinary operation of the municipality. One turbine is the Paludans flak wind turbine? co-operatively owned by citizens in a partnership. Two wind turbines are owned by local farmers, and the remaining two are owned by external, professional investors.

Ballen-Brundby district heating plant(external link). The last straw fired district heating plant starts operation. A shredder takes the straw bales apart and chops it into fine pieces, which are blown into the furnace. The furnace heats up water which is sent to the distribution network and distributed to consumers in two villages. The plant is fully automated, but monitored by a caretaker. The consumers own the plant. The local farmers supply the straw based on a five-year contract.

Samso Energy Agency The EU Save programme, the Danish Enterprise and Construction Authority, and Samso Havvind fund and initiate the Samso Energy Agency. Its objective is to act locally and regionally with respect to renewable energy. Its first tasks are to help establish the Samso Energy Academy, to erect a hydrogen filling station for vehicles, and to promote energy savings by means of home energy checks.

Samso Energy Academy The mayor of Samso inaugurates the new building in May 2007. It houses three energy organizations that promote renewable energy and energy savings. The building is open to the public during the summer period, where visitors get a tour of the exhibition, get a presentation, watch a film, and have discussions with the staff. The Energy Academy organizes workshops, events, and courses for more than 4 000 visitors per year including politicians, public servants, journalists, students, and school children.

General Information about Samso

Fig. 3. Population of Samso. Depopulation threatens the island, and it is one of the major concerns of the municipal board.

The population of Samso is around 4 000 people and decreasing (Fig. 3). The area is 114 square kilometres. Samso is an independent municipality in the administrative region Central Denmark Region, which is one out of five national regions. It is one of the smallest municipalities in Denmark, since after the recent municipal reform the nominal size is 30 000 citizens compared to our 4 000.

People live in small villages or in the open land. The nature varies with areas of open landscape, heath, forest, dune, beaches, and hills. The highest hill Ballebjerg is 64 metres.

The largest economical sectors are agriculture and tourism. The social and health care sector is about the same size counted by the number of employees. There was a fishing industry and a wharf, but today only one fishing boat goes to sea on a regular basis. There are 500.000 tourist overnight bookings per year, and the number is increasing. Two ferry connections link the island, one towards east (1 hour 50 min) and another towards west (1 hour).

Fig. 4. Age distribution of the population in 2010. There is a relatively large amount of old people.

The island has no secondary school after the tenth form, and teenagers who wish to continue their education leave for the mainland around the age of 16. There are relatively few middle aged citizens on the island, and relatively many pensioners (Fig. 4). The municipality recently built a larger home for the elderly, inaugurated in 2009.

Energy supply and demand

The whole island consumes annually about 600 terajoule (TJ) of energy. That is less than one 1000'th (0.1 percent) of the Danish consumption, and it is thus difficult to scale the results from the Samso renewable energy project to the whole country.

The energy consumption per islander is 3/4 of the average Danish citizen's consumption (0.125 TJ or 35 000 kWh compared to 0.161 TJ, see Wikipedia, List of countries by energy consumption per capita). This puts Samso on the level of Ukraine, Italy, and Greece. As an aside, Iceland consumes four times as much per islander.

Fig. 5. Energy consumption 2009. The total consumption is 893 TJ, and the electricity net export is 283 TJ.

The island consumes electricity, heat, and fuel for transportation (Fig. 5). Transportation and heating (communal district heating + individual heating) are almost the same magnitude, electricity is relatively small. The electricity comes sometimes from the cable to land, but on an annual basis the net exchange is export; the windturbines thus produce more electricity than the island consumes. The district heating comes from renewable energy, while the individual heating comes from oil, wood and straw. Solar heating contributes very little, and heatpumps are included under electricity. Transportation, which accounts for 40% of the energy consumption, is almost entirely based on fossil fuel (petrol, diesel). The ferries alone consume almost half the energy in the transportation sector. Transportation is therefore a big problem with respect to renewable energy and energy consumption. It remains to be solved.

Over the years the energy consumption has been steady, despite the depopulation and the closing of the pork slaughterhouse in 2000. Figure 6 shows that initially electricity was imported, but after the erection of the offshore windturbines in 2003, the import went negative (= export). There is still a demand for fossil fuel, but this amount is compensated by the electricity export, and the end result is a 100% renewable island.

Energy balances were made every second year during the project. They contain a large amount of numbers in a spreadsheet for each year. The energy balances keep track of the fossil fuel and renewable energy input to the island, as well as its conversion, losses and end-use. It is a large, valuable piece of work, that documents the transition to renewable energy.

Fig. 6. Energy balance (climate adjusted).

Renewable Energy

Fig. 7. Renewable energy 2005. The numbers are terajoules.

After 2003 the renewable energy is the same amount as the energy consumption. Figure 7 shows that the renewable energy mainly consists of wind power from the windturbines. Next comes straw, which is fuel for three district heating plants, and wood chips, which is fuel for the fourth district heating plant.

Only 35% of the local biomass resources are exploited, and there is a large biogas potential (145 TJ when supplemented with energy crops). There was a biogas plant, but it was closed due to financial problems. There have been several attempts to establish a biogas plant since. Now an action group has been formed, and they are planning to perform a preliminary investigation.

The final project report, the major reference, describes the whole project in more detail (Jorgensen, Hermansen, Johnsen, Nielsen, Jantzen and Lunden 2007).

  1. EDIN Samsø, Denmark, Strives to Become a Carbon-Neutral Island
  2. Energinet.dk Energy net now
  3. Larson J 2009 Island in Denmark produces more energy than it consumes, Worldfocus, series Green Energy in Denmark, Video 6 mins
  4. Map Samso in Europe
  5. Planenergi home page
  6. Samsø Vindenergi I/S home page
  7. State of Green home page
  8. Wikipedia Canola
  9. Wikipedia Joule
  10. Wikipedia Svend Auken
  11. Wikipedia List of countries by energy consumption per capita

Created by system. Last Modification: Tuesday 25 March 2014 18:57:47 CET by jj.