Re: How do these thing save money?
"If you want to save money, don't use electricity/gas, right?"
This isn't about saving money, it about saving the planet, in the minds of the EU, and you are lucky to be allowed to pay for it. You have to bear in mind that smartmeters are mandated to be offered to all consumers by 2020 under EU directive, now written into UK statute by the bunglers of DECC and the criminals of Westminster.
The authors of this policy have committed to it on the basis that (a) they have re-engineered government to a war-footing to fight "climate change", and (b) they earnestly believe that the paltry savings will add up. But you have also to be aware that smart meters enable half-hourly metering, which means potentially different charges based on when you use electricity. Anybody can see that this will be confusing and customer-unfriendly, but half hourly metering is already in the process of being foisted on small businesses. In the short term half hourly metering says nothing about the tariff structure, in practice the tariff follows, and it is the regulator's expectation that the two will be linked (search on Ofgem, P272, filetype:pdf). There's an important underlying hypothesis here that shifting demand around during the day will have a big impact on emissions, and that's wholly unproven.
OFGEM are forever whining that the electricity market "doesn't work" (and it's true it often doesn't but usually because of them), but they are hoping to see energy suppliers experiment with time of use tariffs before smartmeters are universal, and then it will be open season on consumers. As usual the poor will be hardest hit, but I was rather amused to read in a DECC commissioned report that a mitigation strategy for consumers facing higher peak electricity charges that they could cook their evening meals later (like 10pm) to avoid higher peak charges in winter.
Unfortunately, all of this policy ignores the problem that the EU/DECC renewable strategy means that in future years we will have unpredictable generation, so that the prevailing logic of peak demand driving prices will fall apart, and prices will be driven by the random interaction between the vast build out of wind and solar power (again, your expense) and demand.
EU and UK energy policy (including smartmeters) is a despicable, tree-hugger inspired mess. Industry projections are that energy policy will cause electricity prices to double by 2022, and all of the three main political parties have the same position - blame suppliers for the cost of electricity, whilst throwing more and more of your money at subsidies and bad ideas like smart-metering.