An Ofgem report has found that energy companies reach energy efficiency targets in 99 per cent of cases.
Some six million consumers have benefitted from energy-efficient improvements, including 700,000 of the most vulnerable households in the UK. Companies such as EDF Energy, E.ON and RWE npower managed to make their respective goals.
However, major suppliers like British Gas, SSE and Scottish Power will now be under investigation from the energy regulator in order to understand why energy efficiency targets were not met.
These improvements were supposed to be made under government schemes such as the Carbon Emissions Reduction Target (CERT) and Community Energy Saving Programme (CESP).
Ofgem warned companies that they may face enforcement action if targets are not met, which saw many firms increasing their efficiency activity in the final year of the programme.
Senior partner in charge of enforcement at Ofgem, Sarah Harrison, said the regulator's role is to ensure that energy customers do not lose out following the failure of firms to make their targets.
“At a time of rising energy bills, energy efficiency can make a big difference for consumers. The fact that the industry has delivered 99 per cent of its government energy efficiency targets is to be welcomed," she said.
Under the CESP scheme, at least one energy-efficient installation was put into 150,000 homes, including 75,000 benefitting from insulation and 43,000 seeing replacements of their old inefficient boilers.
In total, the CESP and CERT schemes will reduce 312 million tonnes of carbon dioxide emissions via energy-efficient installations throughout their lifespan.
Solar panels could also be an option for people looking to save money on their electricity bills or improve the carbon efficiency of their property.
Whilst some energy companies might not offer solar panels as part of their obligatory energy efficiency improvements, the technology can still be accessed with little cost incurred to the homeowner if the Green Deal is taken-up.
Following an assessment, solar panels, or other carbon efficient technology, can be installed at no upfront cost. The government will provide the homeowner with a Green Deal loan, with repayments on loans made from savings on future energy bills.