Learnings

Outcomes

At the start of the project the TRL was 3. Now the method has been demonstrated on a limited part of the distribution network for a six-month period it can be considered at TRL level 8. For the first half of the closed loop trial period, September 2024 to February 2025, an average voltage reduction of 3% is being achieved. Based on a conservation voltage reduction relationship of a 1% voltage reduction to 1% energy reduction and a typical domestic customer annual consumption of 3,000kWh this equates to an annual energy saving of £23 per customer and carbon saving of 18kg (based on a unit cost of 25p per kWh and a carbon intensity of 270 kgCO2e/MWh). Across the trial area (15,000 customers), this equates to an estimated annual saving of £337k and 280 tonnes of CO2.  

Lessons Learnt

Network voltages are highly dependent on alternate network running arrangements. Therefore any sophisticated voltage management solutions at HV need to take into account the HV network switching topology. 
There are no published accuracy figures for smart meter voltage measurements from manufacturers. Based on limited testing the project determined that ±1% was a reasonable working figure for smart meter voltage accuracy. 
It can be a challenge on internal resources to sufficiently man smart grid projects. They can span multiple departments including OT, telecoms, smart metering, technical services, IT support, IT security and asset management. It can be difficult to get all parties to work together in a timely and efficient manner. Effective project boards with the right level of senior staff are essential. 
It’s unrealistic to take access voltage readings from every smart meter within a primary substation’s area on a half-hourly basis. There are volume and performance limitations both on the DCC/Arqiva radio network and our smart meter gateway, EnergyIP. A subset of smart meters needs to be chosen. 
In our ED2 business plan, Northern Powergrid have committed to rollout the dynamic voltage optimisation concept if this trial is a success so there is a high likelihood that the concept will become business as usual.