Business context
Sector: Civil construction
Location: Auckland
Scale: Small to medium enterprise; 11 staff, supplemented by contractors and subcontractors
The challenge
Civil construction has a significant carbon footprint. Diesel equipment is the norm on New Zealand job sites, and many contractors treat sustainability as a compliance exercise. Kenai Managing Director Caleb Male founded the company in 2021 to do things differently by committing to measure and reduce environmental impacts across every project.
In addition to reducing emissions, two issues drove the decision to go electric. Firstly, working in noise-sensitive and pollution-sensitive environments, such as hospitals and schools, make standard excavators impractical. Secondly, noisy diesel engines make communication difficult, particularly between a machine operator and a spotter looking out for hazards.
What changed?
In 2023/24, Kenai partnered with the Energy Efficiency and Conservation Authority (EECA) to trial a JCB 19C-1E electric mini excavator. New Zealand's predominantly renewable electricity grid means switching from diesel can lower emissions. The trial is also a way to gather real data on how the technology performs on actual job sites.
Kenai matches the machine to jobs where it works best: smaller urban sites where it can return to base or plug into a 15-amp power supply overnight to recharge. At seven to eight hours of runtime per charge, it covers a standard working day. Its compact size means it travels on a trailer, making it practical across multiple sites. All results feed into Kenai's environmental tracking matrix and are shared with clients to support their own sustainability reporting.
Results so far
Two years in, the trial has validated the approach and feedback from projects has been more positive.
- Carbon savings. Since initiation, Kenai’s JCB 19C-1E has recorded 625.3 running hours. Based on an equivalent diesel fuel burn comparison, this represents an estimated saving of 2,189 litres of diesel and approximately 5.87 tonnes of emissions avoided.
- Improved site safety. Reduced noise has made communication between operators and spotters easier, directly lowering the risk of hazard strikes.
- Access to new environments. The machine has opened up jobs in medical and food facilities where fumes and noise were previously a barrier.
- Reduced servicing. Without a combustion engine to maintain, pre-start checks are shorter and overall servicing requirements are lower.
- Positive reception. Workers appreciate the quieter environment and the ability to communicate clearly without a radio. On site, the machine generates interest rather than scepticism.
There have been useful lessons too. Greenfield sites far from power infrastructure remain a challenge, and the total cost of electric ownership needs to account for charging infrastructure, not just the machine itself. Caleb sees this as useful data for the wider industry.
Looking ahead
Kenai is looking at larger electric excavators and other remote power options. Once work is flowing steadily, the next round of equipment investment will go electric where the technology fits.
At a system level, on-site power infrastructure is the missing piece. Caleb sees two paths forward. Developers and infrastructure owners installing power earlier in projects so it is available during construction, or third-party suppliers providing on-site battery solutions. Both require planning and investment from beyond the contracting sector. Larger projects are beginning to specify electric equipment, and as that becomes more common, it creates the scale that makes infrastructure investment worthwhile.
For other businesses thinking about a similar step, Caleb’s advice is practical. Go in with eyes open about infrastructure costs, keep the cost-benefit analysis current and match the machine to the right jobs. The technology works. The challenge is setting it up to succeed.