January 17, 2012. Around 64 percent of consumers using a system to monitor their energy demand at home, so-called smart meters, have made improvements to energy efficiency, a survey by Centrica's British Gas showed. The UK energy supplier, which has installed 400,000 smart meters in customer homes and businesses, also found that 80 percent of the more than 700 smart meter users surveyed said the devices had made them rethink their energy consumption. The UK government has made plans for every household and business to be fitted with a smart meter by 2019, a target that requires the replacement of around 53 million gas and electricity meters.