Church and charity warn on solar
The Church of England and the National Trust have written to the government saying recent policy changes put community solar power schemes at risk.
They fear the changes "signal a retreat" in government plans to move towards localised renewable energy.
This week, the High Court ruled that a plan to halve subsidies for solar panels was "legally flawed", and MPs' committees said it was "panicky".
The church and the charity want a UK target for community energy.
Both organisations have tried to take a leadership role in developing community energy schemes.
They believe this type of project is being unfairly penalised by proposed changes to the feed-in tariff (FiT), the scheme that pays householders and communities a subsidy for producing solar electricity.
Their letter, to Climate Change Minister Greg Barker, is also signed by think-tank Forum for the Future and charitable consultants Carbon Leapfrog.
"I don't think anyone could argue with the fact that the way FiTs were set up created a bit of a market bubble, and economies had to be made," said Patrick Begg, the National Trust's director of rural enterprises.
"But the way the government has chosen to change the models has really shaken confidence - and it's very difficult to be certain that when commitments are made about support for renewables, they're going to stick," he told BBC News.
The letter contrasts the "sudden lurches" in policy and support that the UK has seen with the long-term stability that underpins the success of community-scale solar electricity in Germany.
"Twenty years of solid support has led to 18% of [Germany's] national energy supply now coming from renewable sources, with 45% of schemes owned by co-operatives and farmers," it reads.
"In the UK, this is just 1.5%."
The organisations are urging the government to establish and maintain higher FiTs for community schemes.
Setting an example
The National Trust has about 150 renewable energy projects across the properties it owns, and has set a target of supplying half of its energy needs through renewables by 2020.
It is particularly concerned that in villages it owns, where communities have come together on insulation projects, enthusiasm for extending into solar power has rapidly waned.
The Church of England, meanwhile, says that about 300 churches have so far invested in solar energy, many spurred by the FiTs.
"It's not always straightforward, but a lot of churches thought it was a good opportunity to get involved, to be a good example to the local community," said David Shreeve, environmental adviser to the CoE's Archbishops' Council.
"The changes could affect the financial implications for churches going ahead."
The extent of support for household and community FiTs is currently unclear, with the government having said it would challenge Wednesday's High Court ruling.
It was planning to drop the subsidy from 43p per kilowatt-hour (kWh) to 21p from 12 December. The cut will probably come, but at a later date.
A consultation on other changes closes today.
Among other things, it proposes toughening the criteria on home insulation necessary to qualify for FiTs - a move that was described on Thursday, in a joint report from the Environmental Audit Committee and the Energy and Climate Change Committee, as likely to deal a "fatal blow" to the UK's domestic solar power industry.
Meanwhile, a report from consultants Cambridge Modelling predicts that the changes to FiTs mean it will take longer for solar systems to become competitive with electricity supplied from the national grid.
"In the absence of the changes, small solar photovoltaic installations are set to achieve grid parity by 2019," said Mark Hughes, the organisation's director.
"The changes to the scheme will delay grid parity and extend the need for feed-in tariff support by approximately three years."
Critics have said the cut in solar power support undermines the coalition's claim to be the "greenest ever government".
Mr Begg agreed that it does raise the question.
"The government set out quite a good agenda; and this kind of thing does start to shake our confidence that they are going to make good on their agenda," he said.
In a recent YouGov opinion survey, solar emerged as the UK's most popular energy technology, with 74% of respondents wanting the government to increase the amount in use.
The figure for wind was 56%. Only 16% wanted the use of coal to increase, while 43% preferred a reduction.
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