The Countries That Lead on Plug-In Solar — And What Sun Hours They Actually Get

The number that should surprise you

Germany has approximately 4 million plug-in solar systems installed. The UK has a fraction of that — tens of thousands at most, in a country of similar population and comparable size.

That gap might make sense if Germany were some sun-drenched Mediterranean nation baking under endless clear skies. It isn't. Hamburg gets around 1,000 hours of sunshine per year. Manchester gets about 1,200. Berlin and London are roughly similar. Southern England consistently outperforms large parts of Germany on solar yield.

The sun hours aren't the reason for the gap. So what is?

The global league table (and their sun hours)

Here's how the major plug-in solar markets stack up — estimated units installed alongside their typical annual solar yield in kWh/kWp/year, the standard measure solar installers use to compare locations.

Estimates based on industry reports, national registry data and trade body figures. Units installed figures are approximate.

A few things jump out immediately. The Netherlands and Belgium both have lower average solar yields than the UK — yet both have dramatically higher plug-in solar adoption. Australia has some of the best sun on the planet and still trails Germany by a factor of 40. Italy sits near the bottom despite having roughly twice the solar resource of Germany.

The pattern is clear: sun hours predict solar output, not solar adoption.

Germany's Balkonkraftwerk story

Germany didn't arrive at 4 million units by accident. The Balkonkraftwerk — literally "balcony power plant" — became a cultural phenomenon driven by a specific set of conditions.

German household electricity prices are among the highest in Europe, regularly hitting 30–35 cents per kWh (approximately 26–30p). Every unit of solar self-consumption saves real money, visibly, immediately. The payback arithmetic was compelling before plug-in solar was even properly legalised.

The German government then formalised the market. In 2024, legislation raised the permitted output limit from 600W to 800W, simplified the registration process to a basic online notification, and clarified that plug-in solar qualifies under the country's broader feed-in framework. The bureaucratic friction dropped to near-zero.

Retail followed policy. Balkonkraftwerk kits are now sold in every major German DIY chain — Bauhaus, OBI, Hornbach — the way lawnmowers and power tools are. It stopped being a specialist product and became a normal home improvement purchase.

The result: 4 million units in a country with grey winters and no particular solar advantage over its neighbours.

The Netherlands and Belgium: beating the UK despite less sun

If Germany's story is about scale, the Netherlands' story is about proof of concept. The Dutch have lower solar yields than the UK's south coast — Amsterdam gets around 1,000 kWh/kWp/year, roughly the same as Birmingham — yet they have ten times the per-capita plug-in solar adoption.

Belgium is even more striking. Brussels gets less sun than Edinburgh on an annual basis. Yet Belgium has three times the UK's estimated installed units. High electricity prices (some of the highest in Europe), strong consumer awareness, and clear regulation have done more than extra sunshine ever could.

Japan and Australia: different stories, same lesson

Japan's plug-in solar market is driven by apartment living. With roughly a third of the population in multi-unit buildings, rooftop solar was never accessible to most households. Plug-in balcony systems — introduced under Japan's small-scale solar framework — gave apartment dwellers a route in. Adoption has grown steadily despite complex urban buildings and variable roof access.

Australia is a special case. It has the world's highest rooftop solar penetration — around 35% of homes — and some of the best sun on earth. Yet plug-in solar adoption is modest relative to Germany, partly because rooftop systems are so cost-effective that the plug-in format solves a smaller problem. When your annual yield is 2,000 kWh/kWp and payback on a full system is 3–4 years, the case for a small plug-in kit is less urgent.

This is the inverse of the UK situation. Australia doesn't need plug-in solar as badly because rooftop is so accessible. The UK needs it more — but hasn't yet built the policy and retail infrastructure to match.

Where the UK actually sits on sun hours

The UK's solar resource gets undersold, partly because of the weather reputation and partly because "sun hours" as a concept isn't well understood.

The south of England genuinely performs. Cornwall and Devon regularly hit 1,060–1,080 kWh/kWp/year — comparable to the Rhine valley in Germany or the Rhône valley in southern France. Brighton, Southampton, and Portsmouth are competitive with Munich. Even London and Bristol, at ~1,010–1,030 kWh/kWp/year, beat Hamburg and equal large parts of the Netherlands.

Scotland is genuinely lower — Edinburgh at ~900, Glasgow at ~895, the Highlands at ~870–880. But that's still within 10% of the Netherlands, which has a thriving market.

Here's the blunt version: the UK does not have a sun hours problem. It has a policy lag and an awareness problem.

The 2024 turning point — and where we are now

The UK's BSI plug-in solar standard (PAS 63100) and the associated G98 self-notification framework arrived properly in 2024, giving consumers and retailers the clarity they needed. The EcoFlow STREAM kit became the first UK government-recognised plug-in solar product. Major retailers began stocking kits.

The market is now at roughly the stage Germany was in 2019–2020 — the framework exists, early adopters are buying, but mainstream awareness is still low. Germany went from ~100,000 units in 2020 to 4 million by 2025. The trajectory can move fast once it starts.

The Sun Hours data tells its own version of this story. The most popular page on this site is consistently the UK sun hours guide — people are looking up whether their location gets enough sunshine for solar to be worth it. The answer, almost everywhere in the UK, is yes. The question now is whether they act on it.

Your postcode vs Germany

If you're in South London, Bristol, Birmingham or anywhere in the English Midlands or South, your plug-in solar panels will outperform a system in Hamburg or Frankfurt — cities where Balkonkraftwerk units are bought without a second thought about sun hours.

If you're in Manchester or Leeds, you're roughly equivalent to Belgium's national average — a country with 12 times your per-capita adoption.

If you're in Edinburgh or Glasgow, you match parts of the northern Netherlands. Which has more balcony solar panels per person than almost anywhere outside Germany.

The sun is there. The framework exists. The question is just whether the numbers work for your specific setup — which is exactly what the calculator below is for.

Calculate your plug-in solar savings for your UK postcode →