By Mark Kinver
BBC News science and nature reporter
There are growing calls for gas and electricity meters to be dusted off, brought out from the cupboard underneath the stairs, and given pride of place in people's living rooms and kitchens.
Advocates of so-called "smart meters" say the information provided by the devices can revolutionise the way households consume energy, and can reduce demand by up to 10%.
The domestic sector in the UK is responsible for about one-third of the nation's carbon emissions, and the government has become increasingly focused on the need for greater energy efficiency in the nation's homes.
Tony Blair on Tuesday gave business leaders a sneak preview of the government's energy review.
He said the twin aims of cutting harmful emissions and improving security of supplies meant that "a step-change in energy efficiency" was "back on the agenda with a vengeance".
The electricity and gas consumer council, otherwise known as Energywatch, says smart meters are vital if these goals are to be realised.
"People do get a lot of messages about energy and the consequences to the environment," says Energywatch's head of campaigns, Jonathan Stearn.
"But the one key link that is missing is the ability for consumers to know how much energy they are using.
"At the moment, there is a box underneath the stairs which they cannot make head nor tail of because it is all in kilowatt hours, and a quarterly bill that may or may not mean anything to them."
"If people do not have any idea how much energy they are using, how can you expect them to change their behaviour?"
"Smart meters" is a catch-all phrase used to describe a new generation of devices that have a range of extra functions, unlike existing "dumb meters" that only measure gross gas and electricity consumption in a home.
The extra functions include:
More Associates, a company which designs devices that encourage a better understanding of energy use, has developed a sophisticated prototype.
- Remotely read: These do away with the need for meters to be manually read. Instead, the information is sent automatically to the energy supplier - either via the power cables or a short-range radio link. This scraps the need for estimated bills.
- Meaningful displays: The meters display energy consumption in monetary terms, rather than kilowatt hours, making it more relevant to people. A display can also be positioned in places where the homeowner can see it more easily.
- Internet meters: This technology is described as the "smartest". It allows people to closely monitor where energy is being consumed in their homes, and where it is being wasted; for example, devices left on standby. All of this data can be accessed over the internet.
It shows the amount of energy each device in a home is consuming; how much it is costing; how much energy was used over the past 24 hours; it can even be calibrated to show estimated carbon emissions.
"Three or four years ago, energy companies would say 'that's very interesting but it is not for us'," says creative director Luke Nicholson.
"What has happened over the last few years is that the concern over the looming energy problem means that everyone is now terribly interested in finding solutions."
Mr Nicholson says that although there is almost universal agreement that smart meters are a good thing, there are still a number of hurdles to overcome.
The main technical barrier is standardisation. At the moment, there is a range of different technologies being used.
Energy suppliers are concerned that if a customer switches to a different company the meter will become "stranded" - in other words, it is not compatible with the new firm's system, and has to be replaced.
"There is not going to be a one-size-fits-all meter," says Mr Nicholson, "but there should be a simple protocol every manufacturer has to adhere to that allows different pieces of kit to talk to each other."
He says this will allow the market to remain competitive, while removing the cost of having to replace obsolete meters when customers decide to switch suppliers.
Another uncertainty is over what benefits smart meters actually deliver in terms of cutting costs and emissions.
Energywatch's Jonathan Stearn says there is a direct link between smart meters and changes in people's behaviour.
"When people can see how much energy and money they are saving when they switch off the TV rather than leaving it on standby, they immediately become more engaged in the whole issue of energy efficiency."
Mr Stearn cites a two-year study carried out by Canadian researchers which showed that the combination of real time monitors (smart meters) and price incentives could reduce overall consumption by up to 10%.
However, other studies give much more conservative returns.
The Energy Retail Association, which represents a number of energy suppliers in the UK, welcomes the idea of smart meters but says there are still some "tricky questions" that need to be answered.
Spokeswoman Nicola Bowles says these include who is going to pay for them and what impact they are going to have on consumer behaviour.
"Our findings show that we all need to be more energy aware because, currently, only 3% of people say they will change their long-term energy use if they had a smart meter."
Making the switch
The first major trial of smart meters in the UK was launched in April. Electricity firm EDF Energy, in partnership with fuel poverty charity National Energy Action (NEA), installed the first of up to 3,000 electricity and gas smart meters into customers' homes in south London.
One of the aims of the trial is to see if the meters do lead to people changing their consumption patterns and cut energy bills.
Energy regulator Ofgem recently held a consultation into smart meters, asking whether the benefits outweighed the costs.
"There has been a lot of noise from a number of different sources saying that smart meters have this tremendous potential," says Steve Smith, Ofgem's managing director for markets.
"But there was another group saying that if this was the case then why weren't more people making the switch."
Mr Smith says Ofgem will publish the findings of the consultation shortly, along with its recommendations of what needs to be done if smart meters are to become part of the furniture in an energy efficient home.