Technical potential of 9 to 11 GW

Photovoltaics must expand massively in Switzerland. In addition to building façades, infrastructure facilities, landfills, gravel pits and quarries could also be used. A study by Energie Zukunft Schweiz indicates: The technically realisable potential for PV in this area 9 to 11 gigawatts (GW) in Switzerland. However, political and regulatory framework conditions must be improved in order to tap this potential.

According to the 2020 solar energy statistics published in mid-July, the expansion of photovoltaic systems in Switzerland rose by nearly 50 per cent to a new record of 493 megawatts as compared to the previous year. At the end of 2020, solar panels with an output of nearly 3 GW had been installed, which cover 4.7 per cent of Switzerland's total power demand, which currently amounts to about 56 terawatt-hours (TWh).

To date, nearly all Switzerland's photovoltaic systems have been realised on building rooftops. A great deal of potential still exists here. According to studies by the SFOE, a total of nearly 67 TWh of solar power could be produced on Swiss rooftops and façades.

In order to increase the potential for solar power, additional existing infrastructure and conversion sites, such as landfills or quarries and gravel pits could be used without taking up additional land surfaces. In Switzerland, there are already various pilot projects under way for infrastructure in transportation, energy production and wastewater treatment. The major advantage is the dual use of these sites. At the same time, certain challenges must be considered, in particular increased costs, accessibility and the regulatory environment.

New study indicates potential

In a new study, Energie Zukunft Schweiz with the support of Axpo, IWB and Energieschweiz categorised the infrastructure types for train and road transportation routes, energy supply infrastructure, disposal and protection structures, and conversion sites. These were assessed according to technical feasibility, acceptance, permit authorisation, efficiency and potential (in general and for winter power production).

The study indicates a technical potential of 9to 11 GW for PV on infrastructure facilities and conversion sites in Switzerland. Considering efficiency as well as the current regulatory environment, the realistic potential according to an estimate by the study authors is 1,5 to 3 GW. This corresponds with  50 to 100 % of the total PV output that is currently installed in Switzerland (see above).

Improving efficiency

According to the study there is one key problem in addition to the additional technical challenges for PV systems on infrastructure projects: The economic efficiency of such installations is generally low or not given at all because in comparison to rooftop systems, the investment costs are higher and self-consumption is low or non-existent.

As a result, the political and regulatory framework conditions must be improved: "In most cases, the broad development of this potential requires special subsidies, for example in the form of a higher one-off remuneration as proposed under the revision of the Federal Energy Ordinance, or with other measures to enable the sale of the electricity at cost-covering prices." According to the study, a further measure to increase the efficiency of the projects are auctions with market premiums as called for by Axpo and that are being discussed in Swiss Parliament as a subsidy measure. Other possibilities could be so-called corporate PPAs.

The regulatory environment and the complicated authorisation situation are a further challenge, in particular for the categories of conversion sites and train and road embankments where spatial planning and environmental aspects represent a great obstacle. The study concludes that in order to promote PV systems on these surfaces, a fundamental decision by the cantons or the federal government would have to be taken in order to support these initiatives and simplify authorisation. The announced revision of the spatial planning ordinance by the Federal Department for Spatial Planning (ARE) proposes certain simplifications for PV on infrastructure outside the building zone, which would be a welcome approach.

Based on the technical potential and the authorisation situation, projects on parking areas are the most suitable. Parking areas are particularly attractive owing to the available surfaces and increasing electro-mobility with growing local power demand.

You will find the detailed study here at Energie Zukunft Schweiz (German only)

More about the topic here: Solar energy in the transport sector