Energize Weekly, September 18, 2019
Rooftop solar arrays could economically provide a quarter of the electricity currently being consumed by European Union (EU) countries, according to a study by the EU’s Joint Research Centre.
The researchers used satellite-based geospatial data to calculate the available roof space in the EU – it came out to about 3,000 square miles – and overlaid it with geographical solar radiation data to calculate “solar energy potential.”
That information was twinned with data on the costs of solar photovoltaic (PV) installations in each country to create a “levelized” cost of electricity that can be compared with other types of electricity generation.
“In many EU Member States, the levelized solar electricity can be produced at a lower cost than retail electricity prices,” the study said. The EU, researchers said, has the potential to host several million rooftop arrays.
The study calculated that rooftop solar could provide the EU with 680,000 gigawatt-hours of electricity a year.
That electricity could be crucial in meeting the EU’s target that by 2030, renewable generation provides 32 percent of the electricity consumed. “To achieve this, the EU needs to increase its use of renewables in the power sector by a much higher amount and a significant part of this will come from solar systems,” the study said.
Distributed rooftop solar generation could also help with grid resiliency as power demand grows as transport is electrified with electric cars, buses and trucks.
“Rooftop systems can cover such an increased demand and if designed to produce electricity mainly for local consumption, side-effects such as grid congestion and dispatch cost will be avoided,” the study said.
In assessing country-by-country potential, the researchers found the competitive edge varied with Mediterranean countries having the best solar resource and large countries, such as France and Germany, having the best financing and infrastructure of solar installations.
Italy, Spain, Portugal, Cyprus, Malta, which have the best solar resource, can produce solar electricity for a cost of 6.6 cents (U.S.) a kilowatt-hour (kWh) to 13.2 cents a kWh.
The study found that some countries with a good solar resource – such as Greece, Romania and Bulgaria – are hampered by high capital costs, while rooftop projects in countries with less of a solar resource, such as Belgium and Denmark, have lower production costs due to access to cheaper financing.
France and Germany offer significant opportunities for production at a relatively low cost with a large amount of roof area and competitive financing.
Germany, France, Spain and Italy also have high retail electricity costs, ranging from 18.6 cents a kWh to 33.6 cents a kWh, which makes solar more competitive.
New EU members in Eastern Europe will likely lag in rooftop solar installations as they face barriers to financing, and some have low retail electricity prices.
“Country aggregated results illustrate existing barriers for cost-effective rooftop systems in countries with low electricity prices and high investment interest rates,” the study said.
The analysis calculated that competitive prices for rooftop solar were not found in Romania, Poland, Hungary, Czech Republic, Slovakia, Croatia, Lithuania, Latvia and Estonia.
