- Brief site description:
Raunistal AS (subsidiary of Greta Energy in Estonia) is developing the Purtse Wind Farm with the projected capacity of 48 MW in Ida-Virumaa province, Lüganuse and Sonda municipalities in the northeast of Estonia. The site has a total area of approximately 1500 Ha and is located 2 km southwest of the village of Purtse and 3km south of the Baltic Sea coast. The terrain consists mainly of open fields with a few areas of scattered trees and bushes. The site is flat and to the north of the site the land slopes gently down to the Baltic coast. The land is used for farming. One part (approximately half) of the land is privately owned and the other part is owned by the government. The site planning was approved by the Estonian government, land leases obtained with private land owners.
|Purtse Wind Project
|Up to 48 MW
Ph. I: With 3 – 5 WTGs: 10 MW – 18 MW
Ph. II: With 8 – 10 WTGs: 30 MW – 38 MW
|The project site is located 2 km southwest of the town of Purtse and about 3 km south of the Baltic sea in Ida-Virumaa province, in northeast Estonia.
|50 MVA, 110 kV/330kV main power transformer substation is available for interconnection (built in 2011) at Elering AS’ Püssi substation. Elering AS is the Estonian electricity and gas transmission system operator. The interconnection agreement with Elering AS is still in force and valid. Under this agreement a maximum capacity of 48 MW can be connected. The Püssi substation is located approx. 7 km away from the wind project.
|Commissioned from Garrad Hassan & Partners (UK). About 3 – 4 years of wind data has been collected from two met masts. Wind resource assessment was carried out by DNV GL.
|Wind monitoring masts
|2 x 70m Class 1 Hi Mast system supplied by Nexgen (UK) Monitoring at 4 levels: 70m, 60m, 50m, 40m
|Vavg. At 84m hub height (m/s): 6.5
Avg. air density at avg. hub elevation of 144m asl (kg/m3): 1.245
On site measurement period: 3.7 years
Ambient TI at 15 m/s (%): 11.9
|Planning and Environmental Impact Assessment
|The environmental impact assessment for the project was carried out by Hendrikson & Ko. The Environmental Board has approved the environmental impact assessment.
|50-year land lease agreements with land owners.
|Wind Turbine models
|Decision pending. Various wind turbine models have been evaluated and the decision will be based on technical and other commercial factors.
|Wind Turbine rating
|2 – 3.6 MW capacity wind turbines have been evaluated
|Number of turbines
|13 locations evaluated
|90m – 130m
|84m – 91m
|Tip height restriction
|Production of Electricity
|For Ph. I with five (5) wind turbines, and depending on the make/model, the P50 Net Energy is approx. 45 GWh/year
- Feasibility Study and Wind Measurement
In 2005 preliminary feasibility study for the Purtse project was developed by Garrad Hassan and Partners (UK). As a result of this study and internal economic analysis, Raunistal and Greta Energy concluded that the existing wind conditions on the site and economic situation in Estonia provide strong ground for the development of a wind power project on the Purtse site.
Since March 2006, for over three years, Garrad Hassan conducted wind monitoring campaign for the Purtse site. The first 70-meter meteorological mast was installed on the site in March 2006 and the second one in October 2006. Both were manufactured by Nexgen (UK) and it accounts for possible loss of data due to special weather conditions such as icing.
Reports on the wind monitoring for the Purtse site have shown results that are in line with those provided by the preliminary feasibility study. In addition, the study of correlation between wind measurements on the site and long-term data from other sources confirms the robustness of the results. In March 2008 the project collected 2-year wind data based upon which energy assessment report was completed by Garrad Hassan in July 2008. DNV GL has updated their reports considering additional wind data and evaluation of different wind turbine models, and the latest report was submitted in Dec. 2017.
DNV GL has evaluated several wind turbines and the latest report (submitted in Dec. 2017) for the purpose of estimating the energy production considers wind turbine models from one of the reputed manufacturers. At this stage Raunistal AS is in the process of negotiating with several manufacturers to make a final decision about the technology that will be used for the wind farm. A decision will be taken based on technical and other commercial factors.
- Grid connection
The site is located approximately 7 km away from 330 kV Püssi substation. In January 2008, Raunistal signed an interconnection agreement with AS Elering (the local entity responsible for power transmission in Estonia) for grid connection at the Püssi substation. The interconnection agreement is in force and is still valid. The grid connection point (in the Püssi substation) was built in September 2011 and consists of a 50 MVA, 110kV/330kV main power transformer and other equipment.
- Environmental Impact Assessment
Detailed planning of the site, strategic environmental assessment and obtaining of all required permits was prepared by a local reputable consulting company Hendrikson & Ko. The development and comprehensive planning of Purtse Wind Project was made by Hendrikson & Ko and is based on strategic planning procedures. Permits for constructing Ph. I, consisting of five (5) wind turbine locations, are available and construction can begin anytime.
- Land Leases
For Ph. I consisting of five (5) wind turbine locations, Raunistal has negotiated 50-year land leases with the land owners. The lease agreements are signed and the approval of the detailed planning process was obtained. Land agreement for the wind turbine locations that are on public land has to be finalized with the government agencies and is being pursued.
- Schedule of operations and possibilities for expansion
Construction for Ph. I can commence immediately as the necessary permits are available. For Ph. II, it would depend on the schedule for acquiring land and other permits. However, Ph. II would not be affected by interconnection issues, as the main power transformer in the Püssi substation has the capacity for connecting Ph. II and the interconnection agreement is already in place. Depending on the capacity of Ph. I, the project can be expanded (with Ph. II) by 30 – 38 MW.