As a consultant at Bain & Co, Darbyshire, 31, spent several years advising large companies on renewable energy. But he realised that if change was going to happen, the focus needed to shift from large corporations to helping the UK's 26 million households, which consume 40% of the nation's energy.
'Cracking the domestic market is one of the biggest challenges,' he explains. With his co-founder, Toby Ferenczi, Darbyshire launched Engensa in 2009 to help families cut energy bills and become more sustainable by changing the way they heat and power their homes. 'Sustainability is not just about lowering carbon emissions. It's about enabling society to move to a lifestyle that is neither wasteful nor harmful to the environment,' Darbyshire says.
Engensa's main activity is the installation of solar panels. The company's 100-strong team help homeowners finance, install and maintain the electricity generators, which can cut a household's energy bills by up to £1,000 a year. Engensa's solar panels have been such a success that the company is now turning its attention to boilers and heat pumps. 'Darbyshire has true entrepreneurial zeal,' says Go On UK chair Martha Lane Fox, who was involved early on in the awards.
Darbyshire's values are put into practice at Engensa's west London HQ. It's a critical factor in employee retention, he says. The office is heated with biomass, installation teams drive hybrid vans and Darbyshire gives his employees money to cycle to work. His dedication particularly impressed the judges. 'His entry was the only one to draw attention to the recruitment and retention attraction for a sustainability company,' Carl Gilleard notes.
Darbyshire knows that getting people to think about the way they consume energy will be a challenge: 'We started by helping 100 families a year, now it's 100 families a month. But it needs to be 100 a week. It is really important to keep growing.'
And Darbyshire has faced challenges of his own. Soon after launching Engensa, the government drastically reduced the subsidies for solar panels, bringing many similar firms near to collapse.
It meant consumers now had to pay the £6,000 installation cost upfront. Undaunted, Darbyshire launched an innovative financial plan earlier this year, the SolarLoan. Repayments are now paid over 20 years and covered by savings from their energy bills and a smaller government subsidy.
He is confident that eventually there will be a shift in people's attitude to energy use: 'When you move house, checking there is loft insulation should be as essential as installing broadband. It will happen.'