By Spencer Kelly
New iPhone apps connect with smart meters to tell you your energy use
Saving energy in a home full of gadgets can seem impossible but the latest home energy technology can help you save the planet - and money.
Gadgets such as smart meters are part of the government's plan to cut carbon emissions. Due in your home sometime after 2013, they show you exactly what electricity you are using, and how much it is costing.
They will also communicate with your supplier, automatically taking readings and making switching suppliers much simpler.
But you do not have to wait until the end of the decade to start cutting your consumption.
The Wattson is a simplified smart meter. A sensor clipped onto your fusebox monitors the electromagnetic field in the wires coming from it, and the accompanying transmitter sends the information, wirelessly, to the shiny Wattson box.
It shows how much power you are using right now, and how much that would cost if - rather unrealistically - you continued to keep everything on all day, every day of the year.
It really does show how switching on the kettle, the oven and any other home appliance sends your wattage sky high.
The accompanying software, Holmes, is more useful. It can show usage over time, and settings can be tweaked for a particular energy tariff.
A similar system is the AlertMe Energy Home Hub, which also uses a plug and transmitter.
It connects to the internet using your router, and gives you access to your home's energy statistics via an online dashboard, a handheld controller or iPhone app.
You can get a summary on your iGoogle page by way of the Powermeter widget and the hub also talks to smart plugs, which can be switched on or off remotely.
Smart meters might keep you informed but actually saving the energy - and money - is still down to you.
"Smart meters are not magic. They are a tool and they are like every other tool - you have got to use it and use it intelligently," said Sarah Darby, from the Environmental Change Institute at Oxford University.
"You can take a smart meter round the house, switching stuff on and off, to see what difference it makes to how much [energy] you are using.
"That way, you can see which [devices] are your big users and which are your small users and before you go to bed at night, you can see what is still switched on."
But if smart metering seems like too much effort, one option might be the PassivEnergy management system, which aims to cut your bills with hardly any human intervention.
The system takes over your central heating and hot water controls, using in-room thermometers, a wireless hub, and a new central heating controller to manage your energy use more efficiently.
PassivEnergy takes control of your central heating and hot water system
Initially, you use the handheld controller to tell the system about your normal routine - how warm you like it, when you are usually in and out, when you go to bed and when you are planning to go on holiday.
Then it starts to watch what you do and learn your habits.
Director of market intelligence for PassivSystems, Wayne Muncaster, says this is the clever part of the system.
"You can tell it when you are in, when you are out, and the hot water you believe you need.
"But what the system will learn over time is what your habits are and what you actually do - how many showers you take in the morning, whether you have a bath in the middle of the day. The system will begin to understand your lifestyle habits.
"That means the system will only fire, and actually burn energy when you actually need it, not when you tell it you need it or when you think you may need it, but when you actually begin to use the system."
If you come home unusually early, you can override your settings by pressing the "occupancy" buttons to flip the system from "out" to "in".
And if you decide not to come home at all, you can remotely control the system using an iPhone app.
It is not cheap - the complete kit costs nearly £600, with an annual fee of £20 or £30, although the company says customers can expect to save that amount on their bills in two or three years.
Using technology to save energy in your own home can save you money today, but it could also change the way we power the country tomorrow.
Currently, the national electricity suppliers need to know at any one time how much electricity the country needs, and exactly match it. If they generate too much or too little electricity, the grid will fail.
Smart fridges adapt their electricity use to fluctuations in the national grid
The current solution is to keep several coal-fired power stations running at 50% capacity, so they can be throttled up or down at a moments notice.
It is a very inefficient, wasteful thing to do, but it is the only way to be ready for unexpected surges or lulls in demand.
Now though, clean technology company RLtec thinks it has a solution - the smart fridge.
As commercial manager Joe Warren explained, the smart fridge monitors its internal temperature as well as the status of the national grid - and then compensates accordingly to balance the grid.
"If the grid needs some assistance - if there is too much or too little electricity in the grid - and if the food is at the right temperature, the fridge can turn its motor off or on earlier than it otherwise would have done."
So far the smart fridge is just part of a trial roll-out by energy supplier nPower - balancing the national grid will of course require many, many more people to buy them.
The world may slowly be getting its head around smarter energy and governments are getting on board.
But for at least the next few years - until the devices become mandatory and affordable to all - smarter energy consumption will remain an option only to those who are willing, and able to pay for it.