Initially the dark solar panels were considered to be a constraint, which would be better off on a bright building. Only a very few custom-sized panels were needed to make them fit. Rainwater gutters were suggested to be fully integrated into the eaves. The reason they did not in the end was related more about to general concerns regarding moisture management than due to the solar panels. When the building was put into use, one out of five inverters failed, leading to an installation of a lightning alarm to avoid future production losses. (Mr Daniel Ryman, Skanska)

The project management notes that the question of payback time is never raised for any other part of the building envelope or structure, only for the integrated solar cells. A battery as a night storage unit could have increased the direct consumption of solar generated electricity corresponding to half of the electricity for building use. Since erecting Väla Gård, investments in integrated solar power have not accelerated substantially. More common environmental certifications such as the national ‘Miljöbyggnad’ are dominating. Also other issues such as rain water treatment subjects solar power generation to competition against green roofs.

The overall goal for the project was to achieve a building that annually generated more electricity than it consumed (tenants’ electricity consumption excluded). The initial plan was later changed and the solar installation was extended by more than 50%, almost covering both building related electricity consumption as well as tenants’ electricity consumption. Since the total project budget would permit the extra solar panels, the option of covering the rest of the roof with wooden boards instead was not really an alternative. The price for producing 1 kWh was not the main driving force but instead the goal to minimize the need for externally bought electricity. The governmental financial grant for solar power was not taken into account in the project budget, so this was perceived as a welcome bonus of 45% of the total cost of €300,000. The local energy company and grid owner Öresundskraft is buying exported solar electricity for the average instantaneous price on the Swedish market. Additional income from electricity certificates has not been taken into account in the calculation, since they are considered to be small and unpredictable. The solar installation is calculated to be paid back in 12 years. The major value is said to be that the office building achieves a ‘Plus energy’ brand, a LEED-Platinum certification, and Skanska’s own ‘Deep green’ label. The visibility of the solar installation is also regarded to be a major value. All services are included in tenants’ rental agreement, so no cost or risk due to the solar installation is added.