Civil Engineering

Carbon & Customer Considerate Compounds.

Carnell are working with suppliers to decarbonise compounds and the plant used on schemes for National Highways. This approach has seen us lead the industry in adopting best practices which reduce not only the carbon footprint, but also fuel costs and the effect of noise and air pollution on local communities.



> Low Carbon CompoundS

> Sustainable Initiatives


As delivery partners for National Highways, Carnell are principal contractors on civils, drainage and road restraint projects through the Scheme Delivery Framework (SDF).

To enable effective delivery, site compounds are located close to the work location which include materials and plant storage, welfare and project management spaces.

Carnell have seized the opportunity to make efficiency savings and boost the environmental credentials of our operations through collaboration between suppliers and our site, plant and procurement teams to source increasingly sustainable options.

One of our SDF tender commitments is to reduce our carbon emissions by 2% per annum (Benchmarked against 2019 emissions). This is in line with Carbon Trust guidance and is supported by our corporate ‘Be Sustainable’ golden thread.

National Highways Imperatives


The Home Safe and Well vision is supported by:

  • The use of solar and HVO energy. Reducing harmful emissions at the tailpipe, where site teams are at work.
  • Using rechargeable hand-held equipment which is quieter.

Local residents experience less noise at night and emissions by:

  • Using battery storage units and technology to shut-down generators and plant at night.
  • Using greener alternatives to reduce local air pollution.

Efficiencies are made by:

  • Reducing fuel consumption.

  • Eliminating waste.

  • Harvesting solar and wind power and collecting.

Net zero highways:

Our 2030/2040/2050 plan >


We have less than eight years to achieve National Highways’ ambition for all construction plant and compounds to be zero emissions by 2030.

As it stands, early in 2022, we are only a short way into this journey, but we have made our first steps towards this target.

Using expertise from within the Renew Group, we have verified the savings (shown below and in the centre spread), of a theoretical site compound, which brings together sustainable fuel and plant we have implemented on schemes across the country:

HVO bio-diesel (x500 litres), solar hybrid generator (80kVA solartainer), solar tower lights (x4), solar CCTV security cameras (x1) and solar aided welfare van:

Sustainable Initiatives

From Across Carnell’s Operations.

HVO fuel used to power site compounds

Carnell first trialled Hydrotreated Vegetable Oil to power lighting equipment and site offices in October 2020. Using 4,300 litres of renewable fuel, HVO emitted just 0.15 tonnes of CO2e compared to the 11.1 tonnes expected from standard diesel – the equivalent of two average cars running for a year. In the 12 months since this collaboration with Speedy, 10% of all fuel used on site was HVO.

Compound surfacing using recycled plastic asphalt

In collaboration with Multipave, Tarmac and specialist additive manufacturer MacRebur, Carnell surfaced their A585 Norcross compound using dense binder course material which incorporated non-recyclable waste plastics. The modified asphalt used the plastic waste equivalent of 239,960 single use carrier bags that would otherwise be destined for landfill or incineration.

Electric vehicles & eco run-lock technology

Carnell took delivery of their first all electric van, with charging points installed at Pillaton Yard and Leyland Offices in July 2021, expanding our EV use to include company cars thereafter. Eco SmartCharge run-lock technology minimises the need for our SafetyCam vehicles to idle when in use. The system saves 22k and 10.4 tonnes of CO2e per year, across the fleet of 20 vans.

Recycling Site Waste

Carnell’s landfill diversion rate is around 96% across the business. We use reputable providers to send inert and non-hazardous material to recovery sites where it will be reused for development platforms. One site in Cambridge produced 1550 loads (31,000 tonnes) of waste in six months. Recycling this material and diverting it from landfill saved 514 tonnes of CO2e emissions.


Sustainable In-Situ Filter Drain Refurbishment.

StoneMaster returns roadside filter drains to their optimum condition by removing the sediment that accumulates between the filter media. The in-situ recycling process improves road safety and pavement integrity by reducing flooding events and occasions of standing water on the carriageway.

The process is sustainable in that it recycles existing material and minimises the volume of additional material that has to be quarried and transported to site, thus significantly reducing the number of vehicle movements to and from site. Multiple units can work in the same TM closure for even greater savings and efficiencies.

An analysis of a recent (May 2021) scheme on the strategic road network demonstrated an 81% reduction in CO2e by adopting the StoneMaster process instead of traditional dig-out and replace.

Greenhouse carbon emissions were reduced by more than 21.3 tonnes per kilometre of filter drain recycled.


Mobile road worker protection system


Sustainable In-Situ Filter Drain Refurbishment


Cost-effective risk-based tool which assesses filter drain performance to improve network knowledge