The UK has reached 5GW of installed PV capacity, making it “the most important solar PV market in Europe”, at least during this year, according to the latest findings from analysis firm NPD Solarbuzz.

The UK is only the sixth country globally to have reached 5GW. Germany still leads the pack by some distance with 37GW, while China, Japan, the US and Italy all have over 10GW installed. The nation can now meet around 5.6% of its electricity demand from solar, Solarbuzz says, with 90% of the total amount installed in the past three years alone.

Writing in an exclusive blog post for PV Tech's sister site, Solar Power Portal, Solarbuzz's vice president Finlay Colville said that the high figure makes the UK’s PV market the most important in Europe this year and at the start of next year. This, he says, could help attract inward investment and support.

Colville was clear in highlighting the UK’s support schemes as instrumental in driving the growth of PV deployment, nearly all of which has taken place since 2010. The feed-in tariff (FiT) rates inherited by the UK’s current Conservative-Liberal Democrat coalition government from the outgoing Labour administration were, he says, “among the most lucrative offered to any PV industry”.

Another important driver has been the Renewable Obligation Certificate (ROC) mechanism, which has been behind the recent boom in large-scale PV in the UK. The ROCs scheme is currently under review with an expectation that it will end in April 2015.

“Aside from the answers that economists or environmental activists may wish to offer, the quick and easy answer to the ‘why’ question is incentives. Or more broadly speaking: incentivised vehicles subsidised from the Treasury within which solar technology was allowed to participate,” says Colville.

“It is that simple. Without support from the Treasury, there would have been no solar PV industry in the UK”.

According to Colville and Solarbuzz, while the deployment of large-scale solar has been celebrated in industry circles, PV installations driven by small-scale FiTs “have been the backbone” of UK solar. Around 42% of all UK PV has been incentivised by small-scale FiTs.

Colville also said that where investment from Europe into the UK has tailed off recently, money from Asian and US investors has “flooded in” in quantities great enough to “more than offset” the shortfall. Meanwhile, the strong performance of UK PV in yielding returns for institutional investors has made it compare favourably with more traditional savings and investment vehicles offered by mainstream lending institutions such as banks, says Colville.

Colville also argues however, that the accolade could be a “double-edged sword”. He explains that in his view, it could be a weakness when arguing in favour of keeping top level support for solar.

“Tactically, for example, it does not help in making the case for increased grace period leniency after 31 March 2015, or keeping the sub-5MW ROC option on the table to 31 March 2017. Any grandfathered PV commitment has a long-term Treasury impact on the Levy Control Framework budget.”

Finlay Colville of NPD Solarbuzz's blog on the UK's 5GW milestone can be read in full at Solar Power Portal.