Estonian Enefit Green adds sun and wind to the grid

Less than a year ago, Enefit Green laid the cornerstone for the Purtse wind farm, near Lüganuse parish some 140 kilometres east of Tallinn in Estonia. On 15 June 2023, Enefit Green celebrated the opening of the park.

It is a hot and sunny summer day, and the guests are listening to Enefit’s CEO Aavo Kärmas speech near wind turbine number 10. Though the air is around 25 degrees, it feels much hotter under the direct sunlight. The turbine rises to an impressive height of 150 metres. “The Purtse hybrid park is a significant project for us. The park features the first new and modern wind turbines installed in Estonia in many years”, says Kärmas.

Almost perfect weather

Today, there are no clouds in the sky. Solar parks work on cloudy days, but the panels are most efficient and productive when they are soaking up direct sunlight on sunny days. However, the panels cannot make the most out of extreme temperatures or heatwaves because their efficiency somewhat drops the higher the temperatures are climbing. With the current weather, they produce 230 MWh in a day, and we can call this as an almost perfect summer day for the solar panels. But why just almost? Actually, in Estonia, solar parks usually generate the most electricity in May. At that time of year, the days are getting longer but the temperature is lower than in June-July. Lower temperatures help to increase efficiency.

The visitors can barely feel the wind, but some of the nearby wind turbines’ rotor blades are moving. Today is perhaps not ideal for wind energy production. But unlike fossil fuels, we will never run out of wind.

“A wind turbine starts moving at an average wind speed of 3.5 m/s. To reach the maximum outputs, the optimal wind speed is from 12 to 14 m/s”, explains Kärmas.  

Estonian wind on the rise

Wind power has a long history in Estonia, and Enefit Green’s production history goes back to over 20   years. Since then, renewable energy production and capacity have constantly increased. Yet, opening a new park is not such a mainstream event that you would not celebrate it.

According to Eurostat data, by the end of 2021, there was 259 MW of installed wind energy generation capacities, without significant additions during the last years. On top of that, by the end of 2021 there was 395 MW of installed solar photovoltaic generation capacity, which has grown exponentially from only 15 MW at the end of 2017. Also, the operative statistics suggest that explosive growth in solar capacity installation has been continuing throughout 2022 and 2023. Therefore, the new hybrid park is adding roughly 10% of capacity on both wind and solar generation in Estonia.

“This is certainly a milestone for us in many ways. As already mentioned, it’s the first wind farm built in Estonia for ten years. Secondly, it is the first hybrid park in the Baltic countries, and thirdly, the solar park is the largest solar park for Enefit Green so far” says Kärmas with a smile on his face. 

The new wind turbines have already delivered their first electricity to the grid successfully. Together, the five new wind turbines and nearly 50,000 solar panels provide electricity equivalent to the annual consumption of approximately 25,000 Estonian households.

In Purtse hybrid park, green electricity is generated by a 21-megawatt wind farm and a 32-megawatt solar park. Both power plants utilise the same equipment and connection to the main grid. By combining the variable electricity production from wind during autumn and winter with solar production during spring and summer, the amount of electricity fed into the grid becomes more stable, and the connection is utilized more efficiently. And this really makes sense today: there’s plenty of sun, but as it is often on a sunny day, there’s not that much wind.

NIB loans for Baltic green energy

As a country, Estonia aims to produce as much green electricity by 2030 as it consumes. Wind and solar energy play a key role in achieving this goal. The Purtse park marks a significant step towards renewable energy objectives.

NIB is part financing new wind power generation capacity in Lithuania and Estonia with a loan of EUR 80 million signed with Enefit Green in January 2022. The 12-year loan will also co-finance two of Enefit Green’s wind farms in Lithuania, with total estimated investment costs of EUR 145 million. The two wind farms, Silale II (43 MW) and Akmene (75 MW), are planned to be completed in the first and third quarters of 2023, respectively. In 2023, NIB and Enefit Green agreed on a 12-year loan to co-finance the construction of wind power generation capacity in Lithuania and Finland, and photovoltaic (solar) generation capacity in Estonia.

Enefit Green AS is a renewable energy producer in the Baltic Sea region. The company is a subsidiary consolidating all renewable energy production units owned by the state-owned Eesti Energia group. Since October 2021, the company’s shares have been listed on the Nasdaq Tallinn Stock Exchange.