The budget report from independent body CCC advises the government how much carbon the UK should emit if it is to meet its target of reducing emissions by 80% compared to 1990 levels by 2050. The government must legislate the level of the fifth carbon budget by June 2016, which covers the interim period 2028-2032 and recommends a 57% reduction of emissions compared to 1990.
"Emissions have reduced by 36% on 1990 levels and if current policies are effective will be down by 43-46% in 2020," the CCC said. The legislated fourth carbon budget (2023-2027) dictates emissions must fall by 52%.
The CCC's report said: "It is important that the low-carbon portfolio includes roll-out in the 2020s of offshore wind and CCS [carbon capture and storage] given their long-term importance and the role of UK deployment in driving down costs."
The committee said it had a "reasonable degree of confidence that later-stage technologies (eg offshore wind…) can be deployed at sufficient scale to meet the 2050 target, given a sensible deployment strategy, supplemented by monitoring and evaluation of costs and technical performance, and measures to address financial and non-financial barriers".
The CCC report also highlighted the changes to government policy have hampered new renewables.
Much of the UK's renewable potential was found in the partially-devolved states Scotland, Wales and Northern Ireland, it said. However, it cited a Scottish Renewables report published in early November, stating that Scotland is now likely to miss the Scottish government's 100% renewable energy target by 2020.
"[The] latest projections from Scottish Renewables show that predicted capacity by 2020 will produce 87% of equivalent annual demand for power.
"This is because a number of the projects with planning permission may not have finance in place as they cannot meet the deadline for the closure of the Renewables Obligation and have not yet secured a Contract for Difference.
"There is also greater uncertainty in investment in Scottish renewables following the announcement of subsidy cuts for onshore wind energy from April 2016. With 66% of planned onshore wind farms in the UK located in Scotland, this could have a greater impact on future development than for other areas of the UK," the report said.
CCC's report came one day after the UK government's autumn budget statement and a spending review.
In this, chancellor George Osbourne announced the energy department's day-to-day funding will be cut 22% over the next five years, plus cuts to carbon capture and storage (CCS) funding.
Future funding for the levy control framework beyond 2020 was not mentioned in the budget, leaving the offshore wind and other green energy sectors in continued uncertainty.
Last week, energy minister Amber Rudd confirmed three more contracts for difference auctions for offshore wind would be held by 2020, as long as the industry can demonstrate an undetermined level of cost reduction.
"The [CCC] report also contradicts the UK government’s recent statement to only support the deployment of future offshore wind projects if they further reduce costs by an unspecified amount. The committee clearly argues that it is UK deployment of offshore wind that drives down costs, not the other way around, and that the future energy mix should include the roll-out of offshore wind," said Jenny Hogan, Scottish Renewables director of policy.
Read the Fifth Carbon Budget report here.