Aviva Investors, an arm of the giant insurance group, and HomeSun have completed a deal under which Aviva will acquire the solar developer’s 23MW portfolio of residential photovoltaic systems in a transaction worth around £100m.

The financial details of the deal were not disclosed, but the acquisition gives Aviva ownership of HomeSun’s portfolio and access to the related feed-in tariff payments, which will provide 25 years of returns.

HomeSun added that, under the terms of the deal, it would continue to provide technical support to the households where it has deployed solar technologies.

Homesun was one of the most successful exponents of the so-called “free solar” model, whereby solar developers installed residential PV systems free of charge, giving households access to free zero-emission electricity while the developer retained the feed-in tariff incentive payments.

Prior to cuts to feed-in tariff incentive rates earlier this year, returns from free solar schemes were high enough to attract significant numbers of City investors, allowing firms such as HomeSun to bankroll the rapid rollout of solar panels.

However, the government’s decision to cut the incentives amid concerns over the feed-in tariff scheme’s budget forced many free solar firms to adapt their models and investigate alternative financing arrangements to help make solar deployments more affordable.

HomeSun chief executive Daniel Green said the deal with Aviva represented the culmination of the company’s plan to find “a long-term partner that will continue to provide security to our customers, whose systems will be managed and monitored for 25 years”.