Does dynamic demand hold the key to an effective electricity grid?
Last updated on 5 September 2013, 8:41 am
Existing technologies hold the key to managing electricity demand says the National Physical Laboratory‘s Jane Burston
By Jane Burston
Most people appreciate that there are various means of power generation and these feed into a grid, from which our homes and businesses draw electricity.
The existence of a power station or wind farm ensures the lights turn on when you flick the switch. But few appreciate the finely tuned balancing act that is energy management, or the challenges this poses.
Electricity cannot at present be stored easily, which means generation needs to be well–adjusted to user demand. Electricity generators, distribution network operators (DNOs), and suppliers (the companies we receive our energy bills from) all play a role in this.
Demand swings through large peaks and troughs during the day, the working week vs the weekend, but also throughout the seasons.
During the coldest months in the winter we use heating and make longer use of lights, whereas during the summer, longer daylight means we use less lighting but we may switch on the air conditioning.
The peak demand levels are a problem for two reasons.
Firstly it means strain on the electricity grid. To keep the lights on we need to ensure there is more supply than demand.
Energy companies produce excess capacity to ensure they can cope with the highest possible demand, maintaining a sufficient capacity margin (difference between peak demand and supply).
However Ofgem predicts this margin will fall from around 14% in 2012 to 2-5% by 2015/2016, highlighting the pressure the UK electricity system, partly due to an increase in electricity consumption, and partly because one–fifth of UK power stations are due to close by 2020.
Secondly, renewable energy sources are hard to integrate where demand is at peak. Renewable energy generation is intermittent due to the unpredictable nature of the weather.
While gas can be burned whenever we need it, the wind blows and the sun shines at unpredictable times, which may not be peak energy usage times. In some cases it may even work against us – most lights are turned on when the sun disappears.
Finding ways to intelligently manage demand will help address both of these problems. The government’s commitment to the smart grid opens huge opportunities here – but there are still many challenges.
The smart grid is an ICT–enabled grid that enables the exchange of information and a more integrated management of supply and demand. Intermittent renewable supply can be redirected in a more effective way to areas of demand.
Large-scale work on infrastructure is needed for this shift, and smart meters for domestic and commercial users will be needed in order to make this a success. Smart meters will be rolled out across the country by 2020, opening up huge opportunities for demand management.
A smarter grid and smart meters are not enough. Electricity demand also has to be managed by users in a smarter way.
New smart meters will generate extensive amounts of data. Everyday appliances need to harness this to automatically adapt electricity demand.
These technologies can either shift electricity consumption away from peak hours, or enable greater usage of excess electricity generation from renewables.
There are a number of solutions already on the market.
An energy saving device can be retro–fitted to boilers to place periods of off–time into the heating systems.
Freezers have large thermal storage, so the temperature can be dropped during off–peak times and electricity switched off during peak times. Many new dishwashers already have timing functions that allow deferred running cycles, depending on adjustable settings.
As new data becomes available, there is potential for yet more effective solutions.
Whilst energy management holds huge potential, we must not forget that there are a number of challenges that could yet stop us achieving this.
We need people to actually develop the technological solutions that will shift our energy demand. For this we need to put in place the right incentives.
One commendable attempt comes from Nesta, the UK’s innovation foundation, which is currently running a prize competition – the Dynamic Demand Challenge – to support and fund new ideas that address this problem.
Many people don’t pay much attention to their electricity consumption, which is a big stumbling block. Effective communication and incentives are needed to tackle this.
Incentives are not yet fully understood and we need to find out what works best. Will cash incentives change behaviour or might recognition of the wider societal benefits encourage us to shift our electricity usage to off-peak times in our homes?
Regulatory frameworks are needed to underpin incentives. If regulation prescribed energy management functionality in appliances, or there was a labelling mechanism like the one behind energy efficiency labels, this would drive manufacturers and provide valuable information to consumers.
Standards on connecting to the grid are fragmented. An open, unified standard is needed to establish how and what tools can engage with the grid to allow effective innovation.
In 2012, renewables made up 11.3% of the UK’s energy mix (DECC). The UK government has a target for that to be 15% by 2020. These targets will increase considerably in future decades.
In the absence of efficient large-scale energy storage, we need to find ways to better direct energy from renewable sources and maximise their use if we are to effectively utilise an increased amount of renewable resources. Managing energy demand is major challenge and an often overlooked area in this struggle.
We have a big hill to climb and many parties need to be involved. We need governments to recognise the problem and provide incentives. Energy companies need to price to encourage people to shift demand. Innovators need to develop the technologies that will actually do the job. And individuals need to understand the issue and what they can do about it.
But this is possible. We were once in a similar position with recycling. But thanks to a clear communication campaign, government initiatives to make it easier for people, and carrots and sticks to make people respond, most people now do their bit and everyone benefits.
We want to see similar commitment from government, business and individuals on this issue. If we do, we can reduce energy wastage, reduce emissions and meet and exceed our targets for renewable energy generation.
Jane Burston heads up the Centre for Carbon Measurement at the National Physical Laboratory.
The National Physical Laboratory (NPL) is the UK’s national measurement institute, which means it is a centre of excellence for accurate measurement, science and technology. Follow all the latest developments @NPL