When we combine efficiency and technology we can lower greenhouse gas emissions, provide cheaper electricity and heating, and create a more secure energy supply.
The city centres of tomorrow’s networked world will produce power and heat as well as consume it. The roofs and facades of public buildings are ideal for harvesting solar energy. Efficient energy use will become the standard for all buildings. We will have a diversity of energy sources that are well suited to the needs of the area and in some cases, particularly in developing countries, independent from the national network.
This model of decentralised energy generation, where energy is produced close to the point it is consumed, will provide big energy savings. One of the key technologies that can be used is combined heat and power (CHP) stations. These stations capture the heat produced as a by-product of electricity generation and use it to heat buildings and to power industrial processes, instead of wasting it up cooling towers like conventional power stations.
We also lose between three and five per cent of the electricity we generate when it is transmitted across long distances.
Decentralised energy is scalable and flexible. It can range from a tiny CHP plant in a supermarket or a single wind turbine to enormous industrial plants like Immingham, Europe’s largest, or wind farms like Thanet off the Kent coast.
Decentralised energy also has a key role to play bringing clean energy to about a quarter of the people on the planet who are living without electricity. Renewable energy can easily be harnessed on a small scale, at or near the place where energy is needed. This approach to energy production means that the local system can be designed based on what resources are available locally and what is needed by the people.
It can also be empowering for people by providing them the opportunity to operate and govern their own energy services and stimulating the local economy.
Combined Heat and Power
CHP is the heart of an efficient, decentralised energy system. It’s the most efficient way possible to burn fuel because so little energy is lost as waste heat. That’s how CHP plants in Denmark can reach up to 95 per cent efficiencies.
Because the heat needs to be captured and piped around the local district, CHP plants are usually sited in the towns and cities where the electricity and heat will be used. This makes it more efficient for electricity generation as well as heat; very little energy is lost in transmission.
CHP has enormous potential in Britain, and when combined with improved efficiencies in the home (proper insulation say, and minimum efficiency standards for appliances), would practically eliminate the enormous wastage inherent in our current system.
CHP has a crucial role to play in the transition from a fossil-fuelled energy system to one based on cleaner, greener fuels. CHP plants can run on a variety of fuels, which means that the fuel mix can include fossil fuels like natural gas but, as more cleaner fuels like biogas and biomass become more available, they can switch to those.
Combined heat and power plants can be tailored to fit local needs, allowing us to take advantage of local energy sources. But to make the most of what CHP and decentralised energy can offer, we need to make changes to the way power is used and consumed.
We need a smart grid.
A smart grid is an electricity network which intelligently integrates the actions of all users connected to it – energy generators, consumers and those that do both – in order to efficiently deliver a sustainable, efficient and secure supply of energy.
In traditional power grids, power generation follows how much businesses and people want. But in the near future, technology will allow power consumption to respond to how much electricity is available, with things that aren’t time-critical shifting to periods when more power is available. Using smart meters, smart appliances and energy monitors in our homes, smart grid will allow us to:
- immediately see what we are using online. We can then take advantage of this information to charge our electric cars at night drawing on cheap wind power, for example, or to programme new ‘smart’ appliances like washing machines that can operate at times when prices are low.
- integrate clean energy technologies like wind power where power generation is variable
- create our own electricity (such as from solar panels on our roofs) and sell any surplus back to the grid – thereby encouraging more decentralisation.
Before he was elected, Prime Minister David Cameron outlined plans for a £1bn investment in an energy smart grid, and to install a smart meter in every home. This pledge was again confirmed in the coalition agreement published in May 2010. We’ll be working to hold him to this promise.
Imagine if your washing machine could turn itself on or off to take advantage of off-peak electricity prices. We’re on the verge of a technological leap into smart appliances which do just that.
They use ‘dynamic demand’ technology to monitor second-by-second changes to the national grid. This allows them to switch on when demand is low and electricity is cheap, and to turn themselves off when spikes in demand threaten to overwhelm the network.
The potential savings in energy use and carbon emissions are enormous. If all homes had smart fridges, for example, Britain’s annual CO2 output would fall by two million tonnes, the equivalent of taking 700,000 cars off the road or closing a large coal-fired power station.
Energy companies are already conducting trials with this technology, and plan to offer grants and cheaper tariffs to encourage all households to switch to smart appliances.
The benefits of successful dynamic demand control could be considerable:
- A more efficient and stable power grid
- Significantly reduced CO2 emissions from power generation
- Removing an important barrier to a using higher proportions of renewable energy
- A reduction in the cost of renewable energy
- Lower energy bills for all of us.
See a 60-second explanation here.
Transforming our transport system into a zero-emission transport system is also crucial if we’re going to reduce our dependency on fossil fuels. The good news is that the technologies which can accomplish this are starting to become available.
A new generation of electric vehicles are about to hit our roads – cars and vans that look, drive and feel very similar to the oil-powered models they replace, except that they are practically silent and emission-free at point of use.
Major manufacturers are now introducing cars that can travel over 100 miles on a single charge, and recharge in six hours, making them more useable than ever before. Costs are rapidly becoming comparable with conventional cars – and this is just the start.
But it’s only half of the equation – because emissions savings from switching to electric cars will depend on two crucial factors: how the electricity that powers them is generated; and how successful power companies are in managing what will almost certainly be an increase in demand for electricity.
The clean energy technologies already exist which can provide the necessary power – but we need to start ramping up production to meet the surge in demand, otherwise we end up running electric cars on electricity produced from fossil fuels, and make no CO2 savings at all.
Managing that demand can be achieved using the ‘dynamic demand’ technology already discussed. When fitted to vehicles, this will allow them to recharge intelligently, adjusting the power they use to variations in the demands being made on the grid.