Below are a series of the most commonly asked questions about smart meters:

How do smart meters work?
Smart meters will replace your existing energy meters and work in the same way. The only difference is that a smart meter can send and receive information, allowing your energy supplier to remotely check your energy use.
If you use gas and electricity, you will need to have a smart meter for each energy source.

Will smart meters save me money?
Smart meters on their own will not save people money. Consumers will see reduced bills only if they use wireless energy monitors with their smart meter to monitor their energy use and its cost.
As smart meters will improve efficiency and reduce costs for energy suppliers, the companies may pass on savings to their customers.

What are wireless energy monitors?
Wireless energy monitors can provide consumers with up-to-date information on energy consumption and costs. Unlike a smart meter, which is stationary and may be relatively inaccessible (eg: in a cupboard under the stairs), consumers can use these units throughout the house to monitor energy use.
The combination of a wireless energy monitor and smart meter will help put consumers in control of their energy use.

Will smart meters help me reduce my carbon emissions?
Like cost savings, smart meters will enable consumers to reduce carbon emissions only if they have the information that is provided from a wireless energy monitor.

Will smart meters make by bills and tariffs easier to understand?
Smart meters, together with wireless energy monitors, have the potential to dramatically improve customers’ experiences. But energy companies will still need to take action on simplifying bills, making tariffs more comparable and improving transparency in the energy markets.

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Also see:
Smart meters and the smart grid
How will the smart grid work?
The role of the connected home on smart metering
The down side to smart metering