Lessons from designing infrastructure for solar power projects

9.1.2025

Maveplan Oy has some two years’ experience in the research and design of solar parks. We have designed solar park infrastructure across Finland, in Salo, Tohmajärvi, Lapua and Utajärvi.

Many of these projects are located in former peat production areas, where some of the required infrastructure was already in place, including road connections, basic drainage networks and various water protection structures, for example. There are several peat production areas in Finland that are suitable for solar power projects.

To determine the suitability of various areas, we have carried out preliminary studies to assess:

the existing water protection and drainage structures
the soil and soil type
the thickness of the peat layer (by coarse sampling)

The project operator can prioritise the project areas in terms of infrastructure on the basis of these details. The next step regarding infrastructure design should be to ensure that the project operator has initiated a dialogue with the authorities in relation to the need for a water permit for the project. This may have a significant impact on the project schedule. Some projects only require a drainage notification to be submitted to the Centre for Economic Development, Transport and the Environment (ELY Centre), often proceeding relatively quickly. Others require a permit under the Water Act, granted by the Regional State Administrative Agency, for which the application and processing time may be slightly longer.

To assess the need for a permit, the water management issues in the project area must be investigated. This means assessing both the amount of water present and the water quality, as well as any changes to these that will result from the construction. For construction in a marshland to be plausible, some drainage of the area will be required during construction.

To assess the need for a water permit, we have carried out studies on:

the organisation of water management and conservation
soil acidity (HaSu report)
the feasibility of the area for construction based on various drilling methods

Within the project schedule, more detailed infrastructure plans for the area can be prepared while the need for a water permit is being assessed. The purpose of this planning phase is to ensure that construction in the area is successful and that the result is of high quality.

Working on solar park projects, the construction design areas that we have covered include:

feasibility studies of the area based on various drilling methods
tensile tests to be used as preliminary data for designing the anchoring for panel racks using the Ruf-Pull Tester
plans for roads, storage areas and transformer stations
plans for open ditch drainage to ensure drainage and proper water management in the area
plans for controlled drainage (Controlled drainage is a means of preventing the water level from lowering excessively, resulting in acid sulphate soil oxidation. This stops acidic matter leaching from the soil into the groundwater and being carried into the water body below, where it can kill fish and harm aquatic organisms.)
plans for water conservation structures to ensure that the project’s impact on the water body below is minimal

Based on lessons learned from previous projects, we can say that no two solar power projects are the same. The soil properties and water management solutions in each area require individual assessments and plans.

Learn more about solar park projects in customer stories:
Skarta Energy as a Partner in Solar Power Projects ›
Large-scale solar park project by EPV Aurinkovoima Oy ›

Olli Utriainen
31 December 2024