UK energy use and generation

15/02/18

What you can do: –

• Lobby MPs and government to commit to five yearly energy use and CO₂ emission targets within the 2020 -2050 period to ensure action starts now
• Reduce your own carbon footprint by reducing energy use in the home and by making life style changes
• Invest in community and commercial renewable energy schemes
• Only install renewable energy schemes yourself if they are as efficient as investing in larger schemes

UK energy use

In 2016, the UK consumed 192.8 million tonnes oil equivalent (Mtoe) of fossil fuels (Table 1). Approximately 41 Mtoe of this total was used to generate electricity, if the efficiency of UK electricity generation is assumed to average 37%.

The fossil fuel not used for generating electricity, 152.0 Mtoe, was consumed as fuel; natural gas, oil and coal, used in homes, industry, transport, shipping and aviation.

With most of the spotlight being put on decarbonising electricity production, we often forget we must significantly reduce energy used as fuels. For mobile applications like shipping and flying, this will not be easy.

UK energy use and carbon dioxide emissions

The essential change we need to make is to reduce our carbon dioxide emissions.

Table 1 UK Fossil fuel consumption and carbon dioxide emissions

Carbon fuel used and emissions	Data				Government targets (a)
Year	1990	2000	2010	2016	2020	2050
Fossil fuels use (Mtoe)	213.6	234.8	219.5	192.8
Carbon dioxide emissions (Mt CO2 eq)	799	710	606	466	519	160
Consumption emissions (Mt CO2 eq)	NA	555	555	580 (b)
Total UK emissions (Mt CO2 eq)		1265	1161	1046

^(a) Target required by UK Climate Change Act, 2008; the Scottish target is 42% reduction on 1990 figure by 2020, 463 Mt CO_{2 eq}.
(b) Estimate from 2014 DEFRA figures.

Carbon dioxide emissions reduced from 799 Mt CO₂ equivalent in 1990, to 466 Mt CO_2e in 2016. This shows that by 2016 we had already reduced output to below the 519 Mt CO_2e (35% reduction of 1990 figures) required by the UK Climate Change Act, 2008. However, this reduction was primarily achieved by changing from coal to natural gas to generate electricity. Gas produces significantly less CO₂ than coal. The movement of heavy, energy-hungry, industries such as steel making overseas also reduced UK CO₂ emissions. CO₂ emissions embedded in these consumer goods, termed Consumption Emissions, are shown in Table 1. These emissions should be included in the overall UK emissions. Now that coal is little used, and gas is the main fossil fuel used to make electricity, reducing greenhouse gas output to 160 Mtoe by 2050 means radical changes and real action will be needed.

Proportion of fossil fuel used to generate electricity

Table 2 shows how fossil fuel generated electricity in 2016 is at last starting to reduce and to be replaced by renewables. Fossil fuels still constitute 52% of the energy mix. Renewables provide 24% and this is growing rapidly.

Table 2 UK Electricity consumption and source ^(a)

UK energy generation	Data
Year	1990	2000	2010	2016
Fossil fuel used to generate electricity (Mtoe)	54.2	62.5	65.16	40.8
Electricity (TWh) from:-
Fossil fuels	233.0	268.8	280.4	175.7
Nuclear	58.7	78.3	56.4	65.1
Renewables	5.2	10.1	24.6	79.4
Imports	11.9	14.2	2.7	17.5
Total	308.8	371.4	364.1	337.7

^(a) UK Energy in brief, 2017. Dept. of BEIS, July 2017, pp 48

There is evidence that homes in the UK are using 10% less energy in 2016 than in 2004, but this seems to be technology based (e.g. condensing boilers, more efficient white goods, and LED lighting). We are not making our homes more efficient, flying less or buying small, more efficient conventional or electric cars. The commitment to reduce our CO₂ output to 160 Mt CO_2e by 2050 is a big ask, and can only be achieved by joint endeavour of government, industry, and the UK population. Relying on our politicians endlessly discussing agreements like the Paris accord in 2016, while effectively sitting on our hands, must stop.

The one successful development to date is the increase in renewables for energy generation.

Nuclear power

Nuclear power at present provides 19 % of the electricity used in the UK. It provides a continuous supply to the grid, called base load, as nuclear power stations take longer than gas generating plants to start up and shut down. While an increasing amount of nuclear generation capacity would seem a natural partner to renewable energy, this is not the case (Barnham,2014). If the government decides to increase nuclear capacity, it will vie with renewable energy. Despite it costing the National Grid plc more than renewable energy, in periods when there is surplus generation, nuclear power will probably be kept going while renewables will be switched off.

Community renewable schemes

While the bulk of renewable energy production is being built by commerce, community groups are also involved. As with almost all activities, economies of scale reduce the unit cost of production. It therefore makes economic sense for individuals to club together to install large wind or solar power sites rather than to act alone and build micro generators for their own homes. Two examples of community schemes are described below.

1. Udny, Aberdeenshire, community wind farm

The Udny community came together to set up the Udny Community Wind Farm, with the intention of erecting their own wind turbine. After a great deal of work, the 800 kW Enercon wind turbine was commissioned in May 2011, with a loan from Tridos bank. The company gets Feed-In Tariffs (FITs) for the electricity it produces. The money earned is made available annually for funding local initiatives in the community.

Subsidies in the form of FITs were introduced by government in 2008 to encourage companies and householders to install renewable generation schemes. The FITs are guaranteed for 20 plus years and help make the investment more viable. This “pump priming” has been hugely successful, perhaps too successful, so is unlikely to be available in future.

Mackie’s turbines

While it has not been possible to get the capital costs and energy generated from the Udny site, this information is available from the three nearby turbines, Margaret, Matilda and Mirabel, on Westerton Farm, Daviot, Rothienorman, owned by Mackie’s of Scotland (Table 3). The figures presented assume there were no subsidies, so represent the situation once current FITs have all gone.

Table 3. Costs and income from three 850 kW turbines erected in 2011, assuming all the energy generated is sold to the grid for 7.5 p per kWh (£75 per MWh).

Costs			Income
Capital cost	£3,600,000
Annual costs	Site rent	£40,000	Electricity generated (kWh)	7,352,185
	Maintenance	£40,000
	Interest (at 6%)	£216,000
	Insurance	£10,000
	Depreciation (15 yrs)	£240,000
	Total	£546,000	Income at 7.5p/kWh	£551,414

Source:- Maitland Mackie, (2011). The real rational for renewable energy. pp 25. www.greenergynet.com/scotlands-energy-challenge

The figures above show that wind energy from this site is viable at a selling price of 7.5 p (or above) per kWh (Strike price of £75/MWh).

The site rent could be seen as an additional income as little grazing land is lost to the turbines.

2. Aberdeen Community Energy (ACE) – Donside Hydro Scheme.

In 2015 Donside Community Association (DCA) formed ACE to develop a hydro power scheme in the lower reaches of the River Don in Aberdeen. The adjacent Sanctuary (social landlord) housing development had been going to build a hydro generation plant on the River Don, but decided against this. The DCA were disappointed to see such a worthwhile environmental project being scrapped, so decided to develop the scheme themselves, under the title ACE. The site chosen was at a bend in the river which has a 2m drop (head). It is the same location where Donside Papermill many years ago extracted water from the river to feed its own generators.

ACE appointed Highland Eco-design Ltd, a Scottish hydro power development company, to design and build the plant. The company offered to underwrite the scheme finance until such a time as the community could raise the funds through crowdfunded investments. An initial £500,000 of shares at a target 7% annual return, was raised by mid-August 2016, with the offer being fully subscribed within three weeks. A further £600,000 bond offer, at 4% annual return, was then offered to investors from near and far. The plant has a capacity of 100 kW and produces enough power for an average of 130 homes. It runs almost constantly, except when the river is too low in mid-summer and when shut for technical or maintenance reasons. The community has since received additional funding to design a parkland setting for the Donside Hydro, including landscaping, tree planting and better publicity boards. (The author has a £5,000 bond at the 4% return).

Strike prices for types of power

National Grid UK makes deals with smaller generators on a day to day basis. For large scale future developments like nuclear power stations and large windfarms, they may agree a strike price for a 20-30 year period with the company planning to build and run the plant. This gives the company greater certainty that their plant will provide a return on their investment. The strike price for various types of generating plant (Table 3) gives an idea as to which energy production systems are the cheapest.

Table 3 Strike prices for renewables, nuclear and gas generating plant. (£/MWh)

Energy source Year	2018	2020	2022
Nuclear	–	93	93
Offshore Wind	120	101	75
Onshore wind	65	63	46
PV-Solar	75	67	64
Gas	61	66	72

What is noticeable from Table 3 is how quickly renewable energy is falling in price. Land-based wind generated power being the lowest cost system with solar-pv not far behind. Wind dominates in winter while solar dominates in summer, a perfect match.

Future developments to decarbonize UK energy production

One aim for National Grid plc is to decarbonise electricity production, while minimising the cost of energy to us, their consumers. With the rapidly falling cost of renewables compared with nuclear, this will make renewable companies the preferred power producers. The grid will be used to source electricity when renewables nearby are not available. This may be from renewable energy generators elsewhere in the UK or abroad, or gas fueled power stations. As transmitting electricity long distance results in high transmission power losses, battery storage may also be used to supply power to fill gaps in production. Ellon Musk, of Tesla Cars, California, is actively working on large scale battery installations.

Electricity from the grid will increasingly be used to charge the batteries of electric cars, thereby reducing the use of fossil fuels for transport. These self-same batteries may be able to back up the grid when necessary, when renewables are absent.

In the longer term, we will have to stop using natural gas for heating our homes. Reduced demand for gas can be achieved with better sealed houses and better insulation. When gas is needed, we may use biogas from anaerobic digestion (AD) plants, injected into the gas network. These plants are increasingly being seen on farms, with their familiar domes showing above the trees. The alternative is to use heat pumps to warm our houses. These use electricity to transfer heat from an underground network of pipes, or air source heat exchangers, to underfloor heating in the house.

Where peaks in energy from renewables cannot be utilised on a regular basis, the spare electricity can be used to make hydrogen and ammonia, the former as a fuel for tractors, planes and shipping, the latter for making into nitrogen fertiliser.

For all these developments the grid is key and electricity provides a route to fossil fuel free energy. The self-contained small farm or croft with its own energy supply is not the future.

To appreciate the scale of the change, visit “Sustainable energy- without the hot air” by Prof David MacKay. One can play around with various scenarios in his model, but those objecting to the present wind farms will have to get used to many more.