There has been much in the news recently about wind energy, and it is great to see this amazing energy source being recognised. Onshore wind remains the cheapest form of energy, yet it’s offshore wind that is receiving all of the attention.
On 6th October the Prime Minister, Boris Johnson, reaffirmed a manifesto promise to generate 40GW of offshore wind generated electricity by 2030 (a 10GW increase from the government’s previous target) of which 1GW will come from floating turbines. This statement will give confidence to investors and developers to move ahead with proposals and schemes.
The aspiration will be assisted in the next Contracts for Difference (CfD) auction, which will double the capacity of renewable energy. This scheme has a successful track record of giving long term confidence to investors via a guaranteed ‘strike price’ to the sector, with the result that the sector has grown substantial, with significant price reduction with each auction.
Early responses have been mixed, from welcoming governmental support for the sector, to highlighting key issues and concerns, plus the need for various interventions. These include the need for more frequent CfD auctions, much more funding – £50 billion to be precise, and huge increase in the deployment rate of 4GW every year between 2025 to 2030, a rate of one turbine every year throughout the 2020s. Floating turbines particularly need funding assistance due to their early stage of development. Geopolitical concerns focus on the source of the rare earth metals needed for the turbines.
The expansion of offshore wind must also be accompanied by legislation, strategies and infrastructure to work with the variability of renewable energy. Generation capacity must be matched by the capacity to store excess power in order to balance the variability of the renewable energy generated against the demand for power. These include grid connected storage, flywheels, gravitational devices and smart systems. It includes the generation of green hydrogen from seawater, and new flexibility services based on virtual power plants, those in EV charging schemes or with household storage such as household batteries or smart hot water tanks.
Calling coastal landowners and developers!
Turbines are getting increasingly big. In May, the ‘world’s biggest wind turbine’ was revealed to be a Siemens Gamesa 14MW turbine with a 222m rotor, and 108m long blades. The increasing size of turbines, particularly blade lengths, poses problems for the transportation of wind energy infrastructure via roads. As a result much offshore turbine transportation is done by sea, with assembly on coastal regions close to deployment.
As a result, as part of its drive to generate 40 GW of offshore wind, the UK government has launched a scheme to support large scale manufacturing portside hubs in the UK. Coastal landowners and developers of such hubs are encouraged to contact the government if they have land that has significant quayside capability with connected land holdings to support shore-side construction and storage; space to support multiple manufacturers on site i.e. more than 200 ha behind the quay; and have a have a realistic chance of completing construction or being partly operational by 2023.
On the other extreme of the scale, scientists have developed a tiny nanogenerator called “B-TENG”, which comprises two plastic strips in a tube that move against each other. These strips can scavenge mechanical energy from tiny breezes of only 1.6m/s in any direction, equivalent to zero on the Beaufort scale.
You may be familiar with the generation of an electric charge by the piezoelectric effect – think rubbing a balloon on hair! While this generates electricity, the power output is low. To increase the power output, the researchers explored the higher power outputs of the triboelectric effect where the two surfaces become charged after they are separated, and the resulting power is stored for later use.
In tests, the B-TENG was able to power about 100 LEDs in series and low-power sensors. This type of approach could be used to generate electricity in association with other approaches, and in places where other forms of power are not possible.
How sustainable are the wind turbine structures themselves? Up to 90% of a wind turbine is recyclable, i.e. the metal shaft. However the blades are made of fibreglass and composites which is difficult to recycle. While there are some companies that recycle blades, most end up in landfill sites and the need to improve the ‘material circularity’ has been noted.
It is thought that 2.5 million tonnes of composite material are in use in the wind energy sector globally, and that 14,000 blades could be decommissioned by 2023, i.e. between 40,000 and 60,000 tons. These should not be landfilled, but, re-purposed, re-used or recycled into new products. The collaborative report by WindEurope, Cefic and EuCIA sets out many wonderful suggestions and approaches.
It is encouraging therefore that a new consortium has formed with plans to develop the “world’s first” 100% recyclable wind turbine. The Zero Waste Blade Research (ZEBRA) project will investigate the feasibility of a thermoplastic resin called Elium for wind turbine blades.
Picking up on the geopolitical concerns over sourcing materials needed for turbines – much of the metals needed could come from the huge amounts of waste electrical materials discarded every year. If the UK was to implement a material recycling system, harvesting these valuable metals, then maybe the UK government’s goal of manufacturing 60% of the required equipment in this country could be realised, and also shift us towards a circular economy – not just for wind energy infrastructure, but also electric vehicles and other electric machines.
The growing demand for electric cars
New registrations for battery electric vehicles (BEV), and plug-in hybrids (PHEV), account for more than 10% of total new sales. Electric cars are expected to treble their market share this year. Already, year on demand for BEVs increased by 184%, and have overtaken diesel cars for the first time. There has been an increase in sales by 139% for plug-in-hybrids and 56% for hybrids.
One of the reasons for the increase is due to an EV company car incentive, implemented in the UK in April 2020, which has resulted in a boom of EV leases. The change made was to eliminate the 16% Benefit in Kind (BIK) tax for company car EVs, making them lower cost than ICE cars which still have BIK tax (average of 27%).
A potential future push towards increased EV interest will be a statement by the government, expected in Autumn, on whether bring forward its ban on new fossil fuel vehicles from 2040 to 2030.
In California, the governor, Gavin Newsom, announced on 23 September 2020, that the state will phase out all new gasoline-powered cars by 2035, calling the move, “…the most impactful step our state can take to fight climate change”. Transportation generates more than half of the state’s carbon emissions, and this move is expected to help cut emissions by 35%
One of the many announcements made during Tesla’s Battery Day amongst various approaches to bring down the cost of EVs, was the intention to replace cobalt use in battery cathodes with iron or nickel, made with raw materials found in the US.
The use of cobalt in lithium ion batteries is considered to account for 40% of an EV’s value, so replacing it will help reduce the costs of EVs. It is also a controversial and morally dubious chemical due to its extraction using hazardous mining techniques and the use of child labour. The Democratic Republic of the Congo (DRC) has the largest known reserve of cobalt: more than 70% of the world’s cobalt is mined in this country with many informal workers and child labourers. The mines also have the highest number of human rights allegations, with 31 allegations were recorded between 2007 and 2019.
China’s goal to be carbon neutral by 2060 will need much change and investment, not least a shift in vehicle fuel. Currently 98% of Chinese vehicles are internal combustion engines, so about 59% will need to shift to be electric by 2040 to meet the 2060 goal.
Why don’t EVs have solar panels on them? Well, one of them does: the Sion. This is an EV with a 250km range, with integrated PV and bidirectional charging. The PV area amounts to an astonishing 4 m2 , and because it replaces traditional panels, the use of PV also reduces the weight of the car by 20% The bidirectional charging aspects means the car can be used as a energy source, to partake in vehicle 2 grid or… power a coffee maker.
I hosted a very enjoyable webinar for the CIBSE Energy Power Group on Green Tariffs, PPAs, Offsetting and Insetting, hearing from experts on these topics and exploring the real-world impact. You can access the recording of the event and the slides. The speakers, Sarah Merrick (Ripple), Richard Murphy (The Energy Consortium), and James White (Climate Care), gave an introduction to the topics and busted some greenwashing myths.
Offsetting is a controversial topic, with passionate advocates who claim that it is an essential tool to reduce emissions fast and a way to support climate change adaptation and mitigation measures; while opposers accuse it of greenwashing, allowing the continuation of business as usual approaches, and the difficulty in ensuring long-term carbon sequestration.
Acknowledging these difficulties, a team of leading academics have published the Oxford Offsetting Principles to provide a useful resource for rigorous voluntary net zero commitments, and ensure offsetting helps to achieve a net zero society.
Their four key elements to credible offsetting are:
- Prioritise reducing your own emissions first, ensure the environmental integrity of any offsets used, and disclose how offsets are used;
- Shift offsetting towards carbon removal, where offsets directly remove carbon from the atmosphere;
- Shift offsetting towards long-lived storage, which removes carbon from the atmosphere permanently or almost permanently; and
- Support for the development of a market for net zero aligned offsets.
Encouragingly, India received no bids for 15 of 38 state managed coal mines that it wishes to open up to private companies, in a recent auction. However, coal prices are rising elsewhere, notably in Australia where prices have risen in response to demand from India. And in the UK, Cumbria County Council gave planning permission for the country’s first new deep coal mine, Woodhouse Colliery, to be opened for thirty years and produce as much as 3.1 million tonnes of metallurgical coal a year; time will tell whether the temporary halt ordered by Robert Jenrick, the housing minister, will lead to an overturning of this decision.
Given the rush back to private vehicles as a preferred or only choice of transport because of coronavirus fears, many voices are calling for the legalisation of e-scooters on UK roads, as they are in many other countries, to reduce emissions arising from car use for short trips.
A new energy company
Tesla is now not just a car and battery manufacturer, it is now an energy company! Having acquired a generation licence, Tesla has now become the first party to trade flexible power in the National Grid ESO’s balancing mechanism (BM) from its 7.5MW Holes Bay battery storage plant in Dorset. This follows arrangements by Elexon and the National Grid ESO in September, giving access to the BM to smaller assets such as batteries and distributed generators, to promote competition and reduce prices.
Speaking of hydrogen, In a UK first, the HydroFLEX hydrogen-powered train started operational trials on the mainline railway at the end of September, travelling between Warwickshire and Worcestershire. This is an existing class 319 electric train set fitted with a hydrogen system comprising a hydrogen fuel tank and fuel cell so that it can run autonomously on non-electrified routes. It was developed by the University of Birmingham and rolling stock company, Porterbrook. The train demonstrates how hydrogen can offer a cleaner alternative to diesel trains. An aim is for the train to start carrying paying passengers by the end of 2021, and ultimately replace all diesel trains running on the network.
Words, words, words
In this regular feature, we shine a light on words used in energy circles. Last month, we featured short run and long run marginal costs. This month: inertia!
Traditionally, inertia – vital to the stability of the electricity grid – has come from the kinetic energy in the moving parts of large power generators while they are providing electricity to the grid. The moving parts of all electricity generators rotate at the same frequency to ensure a single frequency for the electricity grid, which is 50Hz in the UK. It is essential to have just one frequency for the electricity grid and keep it consistent, within 1%, to prevent damage to equipment and prevent overloading, from household fuses to high voltage lines.
Frequency must be controlled at all times: if demand is greater than generation, frequency will fall; if there is too much supply, frequency will rise. The National Grid calls upon power producers to increase or decrease power production in relation to frequency signals, and changes needs to be implemented within seconds.
The inertia within spinning rotors has a dampening effect, slowing the rate at which the grid frequency changes, allowing more time for response to take place.
Why does this matter?
The equipment used to generate power generation from fossil fuels (gas, coal) and hydropower offer this inertia allowing more time to respond and balance the grid. Power from nuclear and renewable energy (wind, solar) are not as easy to regulate in terms of frequency. Therefore the need for new services such as frequency stabilisation, and balancing supply and demand are becoming much more important.
Nuclear is not flexible at all in terms of its power output, but can provide inertia. It is possible to regulate solar and wind output to enable an upward frequency response if needed, when there is sufficient resources. However, they have no inertia.
However, while the increase in renewable energy infrastructure into electric grids decreases the amount of inertia available on the system, the fact they are inverter-based means that they can reduce the amount of inertia actually required. This is because such power electronics can very quickly detect frequency deviations and respond to system imbalances many times faster than conventional generators, thereby reducing the need for inertia in the first place. Such inverters can be used across the entire grid, irrespective of whether the solar panel is producing energy. This fundamentally shifts how the system can provide frequency response.
Further, capturing excess energy during times of high output can be supplied when there is little solar or wind potential. Attaching batteries and other forms of storage (mentioned above) add new ways of adding in low carbon, clean flexibility into the electricity system. Power generation sustainable from biomass can also help.
Here’s to an inverter controlled, and storage integrated, clean energy grid!