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Meet IIIEE researcher Alvar Palm

IIIEE researcher Alvar Palm

Local inspiration behind increases in solar power

Installing a solar power plant is increasingly popular among Swedish homeowners. Despite nationally applied policies and subsidies, however, PV systems are much more common on house roofs in some municipalities than in others. When IIIEE researcher Alvar Palm tried to find an explanation for this, he discovered that local electric utilities supporting PV played a crucial role.

Being a renewable energy source, solar power is becoming increasingly adopted. Falling market prices along with subsidies and other policy measures have resulted in a rapid global development, which is expected to increase even faster during the coming years.

Also in Sweden, PV installations are increasing, albeit from a very low level. Homeowners have been encouraged to adopt PV systems by policy interventions, such as an investment subsidy scheme (in place since 2009), and a change in national legislation in 2010 that requires all electric utilities to allow homeowners to connect PV systems to their power grid, which gives them the opportunity to sell their surplus electricity. The PV market in Sweden has doubled, four years in a row.

When IIIEE researcher Alvar Palm started to study the development at a more local level, he soon found that PV systems on private homes are very unevenly distributed among Swedish municipalities, in spite of seemingly homogenous national conditions. Alvar Palm chose to have a closer look at the top 5 municipalities in terms of PV density per capita (Essunga, Berg, Orust, Vaxholm and Sala).

What he found was that the difference could largely be explained by local initiatives to promote solar energy. Most importantly, local electric utilities that had taken an active role in supporting PV, for example by arranging information seminars and selling turnkey PV systems, appeared to play an important role for high adoption rates.

“It was obvious that one dedicated staff member could often have a decisive impact on how the local electric utility worked with PV issues. Since most people who consider installing a PV system contact their local energy provider, the outcome of that communication can be of great importance to the homeowner’s decision”, says Alvar Palm.

Furthermore, peers seem to play an important role, as PV adopters often inspire their neighbours. Such effects can occur through direct communication, but just the sight of a PV system on a neighbour’s roof may also often work as a promoting factor.

Alvar Palm’s study also revealed a positive feedback loop: when homeowners and customers influence their public utilities, they in turn influence other potential customers through promotion initiatives and other activities such as seminars.

So what about the vast majority of Swedish municipalities? How are they doing in terms of solar power?

“It varies, but in none of the 50 Swedish municipalities with the lowest PV diffusion was I able to find a local utility supporting PV. On the other hand, in the municipalities in which PV systems were common, local utilities had often been supporting PV from an early stage, before the market took off. This indicates that it was the commitment of utilities that caused the high adoption rates and not the other way around. If we try to educate utilities, or implement some policy that will make them support PV, that might be a cost-effective way to support the technology, much more so than costly subsidies.”

Facts on PV density among Swedish municipalities by mid-2013

  • Median: 3 PV systems per 10,000 inhabitants
  • Top 3: More than 19 PV systems per 10,000 inhabitants
  • By the end of 2013 less than 0.1% of Swedish households had adopted a PV system

Figure: Map of Sweden illustrating the substantial variety of the per capita PV density between Swedish municipalities.


Text and photo: Sara Bernstrup Nilsson