By Giles Hanglin
In November, Octopus Energy launched a scheme to enable its 1.4 million smart meter customers to earn money by reducing their electricity consumption to help avert the risk of blackouts this winter. With enough customers reducing demand, National Grid Electricity System Operator (ESO) obtains a much-needed resource – flexibility – ensuring that peak demand for electricity matches supply across the grid.
Electricity consumers providing these types of flexibility, or demand response, services to the grid operator aren’t new. Large industrial energy users have already been doing it. But, as we head into the first winter of the energy crisis, with the real possibility of reduced gas supplies, minimising demand for gas to produce electricity among household consumers makes a lot of sense.
Helping the grid accommodate more renewable energy
Grid batteries also perform a similar task for the grid operator by providing flexibility, recharging at times when there is more electricity flowing through the grid, such as at night when offshore wind turbines are turning, and by injecting electricity at times of peak demand, typically in the early evening and morning.
Using natural gas to produce electricity contributes to the higher prices we are paying. Renewable generation sources, like wind and solar plants, are much cheaper to build and to run. Installing batteries on the grid can maximise the amount of electricity flowing through the grid from renewable energy sources. That means we, as energy consumers, can use more kilowatt-hours generated by wind and solar and fewer kilowatt-hours generated by natural gas. In their ability to facilitate more supplies of electricity from homegrown renewable, albeit variable, generation, grid batteries:
– Reduce energy costs
– Ensure the UK honours its net zero targets through decarbonising electricity supplies
– Support energy security
Grid access delays becoming “increasingly critical issue”
But getting energy storage projects onto the grid can take time and requires investment. Referring to findings from grid consultancy Roadnight Taylor, a piece by the Financial Times stated that it can take from six up to 10 years to connect new capacity to regional distribution networks because of constraints.
Grid access delays are becoming an increasingly critical issue, according to the findings of an industry survey published in the Association of Renewable Energy and Clean Technology’s (REA) 2022 Energy Transition Readiness Index report.
Requests each year to connect new capacity have increased from the tens to the hundreds. Transitioning our energy system to one that flows with zero carbon electricity produced by numerous distributed energy resources (DERs) at the end of regional distribution networks naturally entails more demand for grid connections. This trend is only going to be amplified if the UK is to meet ambitious goals to more than double existing renewable generation capacity, adding 50GW of offshore wind by 2030 and 70GW of solar by 2035.
Signs of improvement?
While the situation is far from perfect there are some encouraging signs that National Grid is doing something to address the challenge of grid connection bottlenecks that it has acknowledged.
Several of the battery storage projects within Cambridge Power’s development pipeline are located on distribution networks owned by UK Power Networks. The distribution network operator (DNO) is the UK’s largest, with 28% of GB electricity supply transported via its wires, substations and other infrastructure, situated across London, the east and the south-east of England.
In some instances, our battery storage projects are one of 10 or more applications seeking a connection at the same point, often alongside planned solar farms and other DERs in the area. The new capacity, which can collectively amount to several hundred-MWs worth of export capacity, or load, requires grid upgrades, both at the transmission and distribution network level.
Collaborative approaches by the grid operator and DNOs
Working together, National Grid and UK Power Networks are looking at how some projects, which potentially include our battery schemes, can connect ahead of completion of transmission reinforcement works. This is being done through the development of a Regional Development Programme (RDP). These studies look at the GB electricity network to identify areas of development between transmission and distribution networks in areas with large amounts of DERs.
According to National Grid ESO, the RDPs are designed to unlock additional network capacity, reduce constraints, and open new revenue streams for market participants.
Changes to how batteries are modelled
There also needs to be a change in how battery storage is modelled on networks. Batteries aren’t simply generators or loads since they can be operated outside of peak generation and demand times.
There are positive signs that National Grid is looking at ways to model batteries as 0MW when it comes to export and import stress testing. This is potentially significant as it could eventually pave the way for batteries being able to connect without a new substation or reinforcements to accommodate them since they do not operate as pure generators. Previous studies that focused on the cost-benefit analysis of energy storage include the technology’s potential for deferring network upgrades and enhancing grid reliability.
I cautiously applaud these developments. I say cautiously, because the need to accelerate the transition to a decarbonised power system has never been more urgent.
As a developer of energy storage projects, with a nationwide pipeline of projects in various stages of development, which collectively span southern and eastern England, the north-west and as far north as Scotland, Cambridge Power knows first-hand that grid connection delays are an issue experienced across most of the regional DNOs and the breadth of the GB transmission network. It isn’t simply a problem limited to the congested south. And it will worsen as demand for connections continue to mount.
The smooth progress of grid battery projects hinges on securing a grid connection in a timely manner. It will enable projects delivering these systems to be executed more quickly. In turn, this will bring much-needed flexibility to the grid by accommodating more flows of electricity from wind and solar. More importantly, it will bring additional relief to the spiralling energy costs associated with a carbonised and gas-led GB electricity generation system for the consumer.