About 2.5m of this company’s smart energy meters have been installed in UK homes since it was started by Gary Martin, 38, and Mike Woodhall, 51, in 2010. The Harrogate-based firm designs and manufactures the display units in-house for delivery through energy providers such as Eon, EDF, Scottish Power and Ovo. The government’s smart energy rollout — which requires every household and small business to be offered a smart meter by their energy provider by 2020 — has boosted demand for Chameleon’s products. This helped sales almost double to £19.9m last year.