National Highways' target of a 75% cut in its corporate carbon emissions by 2025 has been reduced to 67% by agreement with ministers. 

Despite this the government-owned company has insisted that the change ‘does not make the target easier to achieve'.

The revised target reflects a change in the way National Highways reports the carbon emissions from its electricity usage.

This news follows a Highways report in March revealing that National Highways under-reported its emissions by using an out-of-date forecast of emissions from grid electricity, rather than ‘actual' data.

National Highways' recently published Performance Report to Parliament 2022/23 states that in 2022/23, its corporate emissions were 44,809 tonnes of CO2 equivalent (tCO2e), representing a 50% reduction from 2017/18. This compares with 37,178 in the company's 2021/22 annual report.

However, the company's 2022/23 Annual Report and Accounts states: ‘In March 2023, we agreed with DfT a change in our KPI reporting methodology to calculate electricity emissions based on the latest (and more carbon intensive) grid decarbonisation factors. This aligns our KPI reporting with Greening Government Commitments.'

The new annual report adds: ‘Our updated target is to achieve a 67% reduction in emissions. This will mean reducing emissions from 90,286 tCO2e (2017–18) to 30,148 tCO2e.'

The Performance Report also notes the change, stating: ‘The carbon intensity of electricity generated by the National Grid is higher than originally modelled at the start of the road period. Therefore, the Department has agreed to adjust the target to 67% against the baseline, reflecting that this is outside of National Highways' control.'

It adds: ‘This does not make the target easier to achieve and National Highways will still need to reduce overall electricity use by the same amount (22%) to meet the target.'

As Highways reported in March, National Highways claimed that a behind-the-scenes deal with the Government allowed it to use adjusted 2019 forecasts to calculate carbon emissions from grid electricity.

However, Highways' investigation suggested that Department for Transport (DfT) was unaware that National Highways was doing this.

Asked which document set out the methodology, to be used, the DfT cited the company's Operational Metrics Manual. However, that document does not state what carbon factor should be used for the operational carbon KPI.