Carbon emissions

We're monitoring and reporting our operational emissions and are taking steps to reduce them as part of our plan to reach net zero by 2050.

Operational greenhouse gas emissions

Emissions from our operations include those arising from energy and transport, as well as from the treatment of our water and wastewater (termed process emissions).

The charts below show our overall yearly emissions (financial year, April–March) across all of our offices and operational sites in Kent, Sussex, Hampshire and the Isle of Wight.

The methodology for reporting meets Defra guidance and is calculated using the Water Industry Carbon Accounting Workbook developed by UKWIR. This method reflects the ‘location-based accounting’ approach. This uses the average carbon intensity of electricity supplied via the National Grid and doesn't reflect the renewable power that we purchase.

We express our results as ‘tonnes or kilotonnes of carbon dioxide equivalent’. We include additional greenhouse gases in our accounting (methane and nitrous oxide) and convert these to the mass of carbon dioxide that would have the equivalent impact. This is based on their global warming potential (i.e. potency).

Net operational greenhouse gas emissions

This chart shows the emissions from the different aspects of our operations. These are calculated using location-based accounting methodology.

Annual emissions per customer

This chart shows our annual emissions per customer served for the last six financial years. With a rising population in the South East and increased treatment standards, reducing emissions is challenging. Despite these factors, our emissions have decreased year-on-year. This has primarily been possible due to the decarbonisation of the national grid, which has reduced reliance on fossil fuels. In addition, we've invested in renewable energy to proactively reduce our emissions. This includes the installation of solar panels to help power our treatment works.

Net operational greenhouse gas emissions

This chart shows the emissions from the different aspects of our operations. These are calculated using location-based accounting methodology.

Annual emissions per customer

Market-based accounting

We use the carbon accounting workbook (CAW) to assess and measure our emissions. This allows us to consistently measure, monitor and report emissions data in accordance with Ofwat’s guidance. It's also in line with the annual performance reports (APR) data collection and reporting methodology, employed since 2012–13.

From 2019, the CAW was enhanced to calculate the carbon benefit from the renewable grid electricity we purchase.

This type of reporting, which includes our green energy purchases, is termed ‘market-based accounting’. Before this, we only used ‘location-based accounting’. This employed the UK grid average emissions values to calculate the emissions associated with our purchased grid electricity.

Our net zero 2050 commitment requires market-based reporting, detailing the carbon emissions associated with our electricity purchase contracts.

While maintaining our historic location-based reporting (graphs above), we've also provided a broader view, which reflects our market-based accounting. The table below is based on Ofwat’s consultation released in May 2021 (Table 2 page 12). In 2023 we also expanded the scope of operational emissions we are able to report.

Focus	Water (tCO2e)	Wastewater (tCO2e)
Scope 1 emissions
Direct emissions from burning of fossil fuels	153	1,475
Process and fugitive emissions	1,163	57,102
Transport: Company owned or leased vehicles	1,134	2,106
Total Scope One emissions	2,450	60,683
Total Scope One emissions by GHG type:		63,133
	CO2 as CO2e	4,769
	CH4 as CO2e	30,034
	N2O as CO2e	28,330
Scope 2 emissions
Grid electricity used by company (Location Based Method)	32,733	58,694
Scope 3 emissions
Business travel on public transport and private vehicles used for company business	61	114
Outsourced activities	1,503	8,936
Purchased electricity – Transmission and Distribution	2,815	5,048
Total Scope Three emissions	4,379	14,097
Total Scope Three emissions by GHG type:
	CO2 as CO2e	16,948
	CH4 as CO2e	993
	N2O as CO2e	528
Gross operational emissions (Scope 1, 2 and 3)
By area (water and wastewater)	39,562	133,474
Overall total		173,036
Exported renewables (generated onsite and exported)		2,883
Emissions reduction from purchased renewable energy (market-based carbon accounting benefit)		81,926
Total net operational emissions		91,152

Our Net Zero Commitment

We have committed to support industry body Water UK’s Net Zero commitment – to become carbon neutral. In 2021, we published our initial Net Zero Plan, confirming our commitment to the Water UK Public Interest Commitment to net zero operational emissions by 2050 (market-based approach).

This was an interim target in our long-term strategy to reach net zero by 2050. We recognise the important role we, and the water sector must play in reducing emissions while balancing this with the need to provide our services at an affordable price to our customers.

Forecasts against our 2050 commitment indicate that our plans up to 2050 will mean we can't achieve net zero without the use of offsets for residual emissions. We face significant challenges in delivering our net zero 2050 commitment. These challenges are both in terms of feasibility and deployment.

We believe the best value to our customers will not be served by purchasing external offsets and our strategy isn't to purchase these on the external market. As an alternative, we're continuing to explore how we could support medium- to long-term carbon sequestration through our strategic land management plan and nature-based solutions. We're working with the wider water sector to understand the range and scale of carbon offsetting opportunities.

Our Net Zero Plan sets out our journey towards zero carbon and how we can work with our partners to find sustainable solutions.