climate change


Design out CO2


30% reduction in CO2 per tonne of product compared to 1990.

"Using waste from other industries as fuel for our cement kilns is an excellent way both of contributing to the circular economy and of reducing CO2 emissions. "

Mike Eberlin, managing director, Cement and Lime


Addressing climate change is a cornerstone of our approach to sustainability.

We are making progress right across our business and supply chain, using a whole life-cycle approach to design CO2 out of our products and services. This includes working with suppliers to reduce CO2 from the goods and services we buy, cutting CO2 from our operations and transport, innovating lower CO2 products, services and solutions that reduce CO2 from the construction process or during the use of infrastructure and buildings.


CO2 reduction per tonne of product since 1990
73,000 tonnes
Waste derived fuels used
Thermal input from waste derived fuels
Energy efficiency programmes

We have continued to embed the ISO 50001 energy management standard across our business throughout 2018. We use this standard to drive continuous improvement in energy and CO2 efficiency. We set every site a specific energy and CO2 target and require each to generate an energy reduction opportunities assessment.

This process is supported by the sharing of best practice energy efficiency measures across relevant operations. Our ISO 50001 system helps us to ensure all our operations are compliant with regulatory requirements, such as the UK government’s Energy Savings Opportunity Scheme (ESOS).


Using lower CO2 fuels

Our Cement business has maintained its focus on the use of waste-derived fuels, especially those that have a biomass content. This helps reduce CO2 emissions arising from our cement manufacturing process. By using waste-derived fuels we not only reduce our CO2 emissions, we conserve valuable natural resources and help to reduce the amount of waste that goes to landfill. In 2018, 34% of the heat input to our cement kilns was produced from waste-derived fuels, including 12.3% from biomass. The types of fuels used across our cement operations now include waste tyres (whole or chipped), solid recovered fuel (SRF) from non-hazardous materials including paper, cardboard, plastics, textiles and waste wood chips, recycled liquid fuel, processed sewage pellets (PSP) and polymer chip. Fuels such as waste wood chips and PSP are 100% biomass while tyres, SRF and polymer chip contain a proportion of biomass. The use of fuels containing biomass makes a significant contribution to reducing CO2 emissions as biomass is considered carbon neutral.

We also utilise landfill gas from a neighbouring Viridor site at our cement plant at Dunbar, Scotland and within our materials business we have continued to convert our asphalt plants to lower CO2 fuels, for by switching from the use of gas oil to natural gas or LPG.


Reducing transport impact and emissions

We continue to work hard to optimise our use of transport and utilise a range of  methods to transport product to our customers in the most efficient manner. The nature of the construction sector means that moving raw materials and product by road transport often remains the best and most energy efficient option. It’s therefore  important to ensure we use our vehicle fleet effectively; sourcing from the nearest supply and maximising vehicle payloads to minimise the number of trips required. We have a rolling programme of upgrading the vehicles used by our contract hauliers and require them to move to new vehicles with the latest generation of Euro VI engines.

We have invested in high tech fuel monitoring equipment on our marine dredging vessels to ensure we have the best possible understanding of our fuel use on board.

We also understand the need to minimise exhaust emissions to meet current and planned low emission zones in cities. This is already well established in London, with an ultra-low emission zone and with other local authorities across England set to follow in creating their own low-emission zones.

Our rail strategy has a big part to play in reducing emissions in urban areas and we have increased the volume of material moved by rail this year by continuing to invest in new rail handling facilities and rail sidings. For example, we are now running 15 more trains a week, through new routes and have reconnected sites with rail capabilities at our sites in Port Talbot, Bristol and Thrislington.

Future Innovation

We’re working in partnership with researchers and others in our industry to develop solutions for capturing CO2 emissions in the future. Approximately 70% of CO2 from cement production is generated from the chemical reactions (process emissions), the other 30% coming from the fuels (combustion emissions). The process emissions are difficult to reduce. We are therefore looking into ways to capture carbon and use it to make downstream products or transport it for storage in bespoke facilities, such as old gas fields.

Transport efficiency and telematics

A significant proportion of the constituent materials used to make our products are purchased local to source and road transport is often the most appropriate mode of transport. We continue to work hard to improve the way we use our vehicles. This has included maximising payloads to minimise the number of trips required. We also try to ensure where possible that we supply from the nearest available unit and plan delivery routes to avoid congestion. We regularly upgrade our fleet and are encouraging our contract hauliers to move to the latest generation of Euro VI engines. We have also invested in high tech fuel monitoring equipment on our marine dredging vessels to ensure we have the best possible understanding of our fuel use on board.

In 2017 we continued to invest in our rail facilities delivering on our commitment to transport more of our products by rail. In 2017, we opened a brand new rail aggregates handling depot at Garston, South Liverpool. This new operation, created in partnership with Freightliner and Rail Freight Services provides an additional 300,000 tonnes a year aggregate handling capacity, supplying customers in Merseyside and Cheshire. In 2017 we moved over 9 million tonnes of product by rail - the equivalent to removing 450,000 lorries load from our roads.

Product innovation

We continue to support our customers and end users to create more energy efficient, lower carbon buildings and infrastructure by considering the whole-life (capital and operational) carbon associated with our products by redesigning and rethinking the way we make them. Among options we consider are:

  • improving durability, meaning that products need to be replaced or maintained less frequently -  Read our Ultigrip case study.
  • using recycled or secondary materials in products, such as ground granulated blast furnace slag and fly ash instead of clinker to reduce the capital CO2 in cement or used road surfacing (Recycled Asphalt Planings) instead of primary materials in asphalt
  • creating new products that have a lower carbon footprint – such as
  • providing customers with product carbon footprint information generated from our calculator tool that measures carbon across a project enabling better choices about design and what materials to use. Read more on
  • raising awareness of the benefits of our materials in use through Solution Guides. Read our low carbon solution guide here.

Tarmac is a key signatory of the UK Government’s Infrastructure Carbon Review (ICR) which aims to cut 24 million tonnes CO2 from UK infrastructure projects by 2050. In support of the ICR we have played an active role in the development of a new publicly available standard PAS 2080, the world’s first specification for Carbon Management in Infrastructure. Read it here.

Reducing our footprint

At the end of 2018 we had achieved a 24.1% reduction in CO2 per tonne of product compared to 1990. Our next milestone is to achieve a 30% reduction in CO2 per tonne compared to 1990.

We categorise our greenhouse gas emissions into direct and indirect sources in line with the Greenhouse Gas Protocol.

What we mean by CO2e

Carbon dioxide is one of six greenhouse gases that are emitted when humans undertake certain activities. Other greenhouse gases include methane, nitrous oxide and ozone – all of which occur naturally in our atmosphere. To take into account the emission of other greenhouse gases when calculating the level of greenhouse gas emissions, scientists have devised an equivalent measure – CO2e (which literally means carbon dioxide equivalent). CO2e allows other greenhouse gas emissions to be expressed in terms of CO2 based on their relative global warming potential (GWP).

So when you see a carbon footprint expressed in terms of CO2e, you can know for sure that all greenhouse gases have been included for each activity under scope, and therefore a fuller picture of an organisation's impact has been captured.

Tarmac: CO2 emissions by scope

1000’s tCO2e %
Scope 1 2,362.2 84.4%
Scope 2 143.5 5.1%
Scope 3 294.0 10.5%
2,799.6 100%

Tarmac: Direct and indirect CO2 emissions

tCO2e %
Process emissions 1,326,010 54.8% 
Coal 341,982  14.1%
Electricity 143,471  5.9% 
Waste derived fuel (WDF) 111,850  4.6% 
Natural gas 204,635  8.5% 
Gas oil 128,141  5.3% 
Petcoke 48,760  2.0% 
Processed fuel oil (PFO) 40,431  1.7%
Kerosene 19,202  0.8%
Marine Diesel 19,350  0.8% 
Liquid Petroleum Gas (LPG) 35,861  1.5%

Tarmac: Energy use by source (GJ)

Energy use by source (GJ) %
Coal 3,628,703  24.8%
Electricity 1,824,632  12.4% 
Waste derived fuel (WDF) 1,211,009  8.3% 
Natural gas 4,140,446  28.2% 
Gas oil 1,682,709  11.4% 
Petcoke 520,790  3.5% 
Processed fuel oil (PFO) 543,289  3.7%
Kerosene 278,998  1.9%
Marine Diesel 238,000  1.7% 
Liquid Petroleum Gas (LPG) 597,422  4.1% 
Total 14,665,998  100.00%