The energy and climate change minister at the time, Charles Hendry, told the House of Commons:
"We believe that people will benefit from having smart meters, but we will not make them obligatory. If people are concerned about the electromagnetic issues, they will not be required to have one. We have been willing to give assurances to Hon Members on that account."
The Register also checked with the (now defunct) DECC government department, where a spokesman informed them:
"This is not actually new. While smart metering brings significant benefits, it will not be an offence for householders to refuse to accept a smart meter and we have made it clear that we do not expect suppliers to seek an entry warrant simply to fit smart metering equipment."
Apparently they were intended to be compulsory when Labour's Ed Miliband first introduced the idea, but few, if any, smart meters would have been installed by the time Labour lost the 2010 general election.
But as noted in the previous post, the UK energy suppliers tend to behave as though installation of the new smart meters is effectively compulsory. For example, British Gas recently announced that their electricity prices (they supply electricity as well as gas, for non-UK readers) would go up by 12.5% in a press release:
"Since our last price rise in November 2013, some costs have risen steadily -- among them Government policies to subsidise renewable energy, social levies, delivery to customers’ homes, and the nationwide smart metering programme. In that time, overall electricity costs have increased by 16%."
It sounds from the above that British Gas are charging all their electricity customers for smart meters, whether they have a smart meter installed or not.