The weekend read: Past the Arctic Circle, one degree at a time

Like English ivy climbing a brick wall, in the past decade PV has silently crept further northward in Europe: from Germany and the Netherlands, to Denmark, then Sweden, and now even Norway and Finland, all the way past the Arctic Circle. Especially for prosumers, solar is proving a popular way to bring down electricity bills – and to show off one’s green credentials in the environmentally conscious northlands.

Finland is the last of the continental Nordics to discover solar – about a decade after Denmark broke the ice. From the top of Helsinki Airport Terminal 2, Johanna Kara of Finavia Corp., the state-owned company that operates the facility, explains that solar modules occupy ever greater swathes of the rooftops and facades of Finland’s largest aviation hub. In August 2017, Finavia’s bolting of 396 Indian-made panels on the building’s eastern roof was seen by some observers as symbolic posturing at best, greenwashing at worst. After all, aviation is responsible for about 4.9% of man-made global warming, according to Transportation & Environment, a Brussels-based nonprofit organization, and critics suspected that Finavia wanted to do something to wipe away the stain.

Emission-free airports

But just a year later, counters Kara, the Helsinki Airport, as well as Finland’s 22 other airports, went climate neutral. She says that the terminals’ high carbon accounts are balanced by buying carbon credits from a Gold Standard-certified project that improves the energy efficiency of small houses in Ghana. But the end objective of Finavia’s climate program, she insists, is to completely eliminate all of its airports’ carbon emissions.

The country’s largest airport appears serious about going green. Standing atop its new west wing, we look out over the runways across a brand-new patch of 1,034 rooftop modules (with 15-degree tilt angle) – about three-quarters of the airport’s current 344 kWh capacity. The building also has solar covering the wing’s vertical southeastern facade. And there’s more to come: a sprawling new parking house, currently under construction, will be decked with panels, nearly doubling the site’s solar capacity. That said, Helsinki Airport purchases the lion’s share of its supply from wind power on the Nordic electricity markets.

Regional expansion

Despite all of the additions, onsite renewables capacity still only provides just 1% of the airport’s (growing not shrinking) electricity needs. Indeed, the Nordic countries – Sweden, Finland, Denmark, Norway, and Iceland – only cover a very small share of their power supplies with solar, or roughly as much as the share of the Helsinki Airport. But the north has, in very short order, transformed itself into a dynamic, lucrative market for solar tech – above all for PV systems designed for household and commercial self-consumption purposes. Installed capacity has jumped from almost nothing in 2010 to more than 1.5 GW by January 2019. In Sweden and Norway, installed solar PV capacity more than doubled from 2016 to 2018. But in Sweden, only a sliver of those projects are utility-scale arrays, and in Norway there are none at all.

What started out as an eccentric gesture in cold, snow-bound, often dark countries has morphed into a mini boom. “Even just five years ago,” says Asbjorn Stoveland of Sweco Norway, an engineering consultancy involved in renewables, “solar wasn’t on the map as far north as Norway. It didn’t make economic sense – now it does. The payback times are getting shorter and shorter.”

“The Nordics’ PV markets are developing nicely,” says Michiel van Schalkwijk, northern Europe’s point person for Solarwatt, a German PV module and battery supplier. “Solar electricity is among the cheapest sources of electricity at end-customer level, even in Europe’s most northern countries … there is a good market for sturdy, high-quality solar modules.” However, he notes that batteries are another story – that is, they need investment rebates.

The Nordic countries, long trailblazers in renewables and flexible grid systems, have recently added solar to their quiver, and are deploying it at pace. Studies show that the potential for distributed renewables, particularly for self-consumption, has barely been tapped.

“Distributed generation and self-consumption is increasing as an alternative and a supplement to conventional, centralized electricity production,” according to a new study by Nordic Energy Research, a platform for cooperative research and policy development. In terms of self-consumption, PV constitutes about a fifth of renewables in the Nordics – well behind onshore wind, but ahead of bioenergy and hydropower.

For years the Nordics were considered too far north for solar to be worthwhile. But in addition to falling costs, it turned out that these countries were a good fit for other reasons, not least their green conscience. Also, although winters come with just a few hours of midday sun and plentiful snow, summer days can be 22 hours long – enough sunlight for a rooftop array to supply a medium-sized commercial enterprise with all of its electricity.

Moreover, the fact that the Nordics can be quite chilly, even in spring and fall, is particularly conducive to PV power output, which decreases when cells are overheated. “Voltage increases when the weather is cold, and this makes the cells generate more output,” Norwegian scientists noted in one 2018 study.

Going vertical

The Nordics have also proven to be a successful testing ground for vertical solar – namely, PV installed on building facades. For one, the solar facades are more effective at catching the north’s low-slung sun from spring to late fall. But the Nordic pioneers were also surprised to discover that vertical PV walls also capture reflected sunlight from the snow. And in Finland, one building owner told pv magazine that he covered one building’s new facades with solar panels because it was just about the same price as the expensive facade material he would otherwise have to buy.

“We’re not too far from integrated solar applications that serve as roof tiles,” says Sweco Norway’s Stoveland, who advises Norwegian communities on renewable energy. “Then there’d be no payback period at all.”

Solar companies like European Energy, a renewables developer outside of Copenhagen, say that the Nordics’ high-tech literacy, transparent local regulations, and limited constraints on agricultural space are a distinct advantage compared to southern Europe. “We can use farmland, abandoned airfields, former industrial sites, and the like,” says Jan Vedde of European Energy. However, he adds that one downside is that grid connections in such locations can be scarce and time-consuming to secure.

And, finally, the Nordics’ flexible, cross-border transmission grid and diverse energy palette make solar a natural and easy addition. In the winter months, for example, it’s easy enough to rely on alternatives: biomass in Denmark and Finland, hydropower in Norway, and wood in Sweden. All of the Nordics, with the exception of Norway, still depend on fossil fuels for baseload energy; Sweden and Finland have nuclear reactors.

Despite all of the perks, solar will never serve as the cornerstone of the renewables supply, argues Lutz Mez, a renewable energy expert at Berlin’s Freie Universität. “It’s still not cost effective enough. Onshore and offshore wind, hydropower and biomass are still much cheaper with regard to the investment cost per reduced ton of CO2 reduction. Without incentives of some kind, such as the net-metering statutes that fueled the Danish solar boom in 2010-13, you’re not going to see sweeping adoption of solar PV. It leveled off very quickly once the lucrative net-metering incentives were rescinded,” he says, referring to Denmark. A cost-benefit analysis, Mez argues, shows that investing in energy efficiency in the north brings more savings on electricity bills per euro than the purchase of a home solar package. Indeed, the two factors most crucial to rolling out solar in the north are incentives and domestic energy prices, he says.

In Denmark, electricity costs are the highest in Europe, which is why solar has achieved grid parity, says van Schalkwijk of Solarwatt. The leveling off of the solar boom in Denmark is temporary, he says – a product of the negative press surrounding the scrapping of the incentives.

As for Norway, where power prices are very low – a consequence of the country’s plentiful hydropower – solar has a market because all new housing requires some element of energy production, including solar.

The hottest market at the moment is Sweden, which has a rebate program for commercial and household solar. In 2018, the country deployed a record 180 MW of residential and commercial solar capacity. In 2021, it will replace its rebate program with a green tax deduction.As for utility-scale solar parks, the Nordic market still offers slim pickings. Only in Denmark can subsidy-free solar compete with the other renewables or fossil fuel sources on the open market.

And this year, two small parks in southwestern Denmark began operations. Vandel 3, a much larger park – in fact, the seventh largest in Europe – will begin operations in 2021. As big as 250 soccer fields, it is being constructed on a decommissioned airport in Jutland, Denmark. The estimated annual production is 152,000 MWh.

Snow loads

However, the Nordics’ extreme climates, particularly in winter, require heavy-duty panels. Early pioneers report that module frames can buckle under the weight of heavy snowfall. There is still discussion in Europe’s north about whether it is worth the effort to remove snow from Nordic solar systems, or to simply to ignore it and hope for an early spring.

From the top of Helsinki Airport Terminal 2, Finavia’s Kara says the company is also concerned about snow, but it doesn’t clear it. She points to the terminal’s main entrance, with its sloped roof, where suitcase-laden travelers come and go beneath. “There, we’re not putting up any rooftop panels,” she says, pointing to the roof. The airport’s fear is that the arrays could collect large amounts of heavy snow and precipitate the roof’s collapse. Trial and error will show northern solar the way.

By Paul Hockenos