Trusted on Site. Grounded in Delivery.
Onsen was founded to help deliver better ground source heat pump (GSHP) projects. Today, we support commercial projects across the UK with the drilling, testing and technical expertise needed to underpin the transition to decarbonised heating.
Our Purpose
Ground source heat pumps are becoming an established part of the UK's low-carbon heat future. Delivering successful projects requires specialist expertise at every stage, from site planning and thermal response testing through to borehole installation.
As adoption of the technology has grown, so has the need for specialist drilling, testing and technical expertise.
Onsen was established to help meet that need. Today, we support commercial ground source heat pump projects across the UK through borehole installation, thermal response testing and technical consultancy, working closely with project teams from planning through to delivery.
The Meaning of Onsen
In Japanese, onsen refers to naturally heated water that rises from beneath the earth’s surface. We chose the name because it represents the untapped potential beneath our feet.
Across Japan, geothermal energy is harnessed to generate renewable power before the naturally heated water is used in traditional onsens. This journey – from geothermal source to renewable power generation and finally to the onsen itself – shows the remarkable potential of the Earth's natural heat.
Our role is to help harness that same potential responsibly through ground source heat pump systems, supporting the transition to low-carbon heating and leaving a better future for the generations that follow.
Specialist Expertise. Trusted Delivery.
The values we set for ourselves and bring to every project.
Quality Without Compromise
We take a methodical approach to every project, combining technical rigour with a strong focus on safety, accuracy and consistency.
Expertise That Adds Value
Our team combines practical experience with specialist knowledge across drilling, testing and ground source heat pump systems. We provide the insight and support needed to help projects move forward with confidence.
Raising Standards
We're committed to continuous improvement, investing in our people, equipment and technical capabilities. Through our work, we aim to support better ground source projects and advance best practice in the industry.
Why Clients Work With Onsen
Commercial Experience
Supporting large-scale ground source projects across a range of sectors and site conditions throughout the UK.
Specialist Capability
A strong understanding of geothermal energy systems, providing the technical insight and engineering expertise to support robust, efficient system design.
Long-Term Partnerships
Working closely with contractors, consultants and developers to support successful project delivery.
Proven Track Record
A strong, established history of delivering projects safely, efficiently and to programme.
Our Core Team
Onsen is built on the knowledge, experience and dedication of its people. From drilling specialists and engineers to project and operations teams, everyone plays a role in helping projects run smoothly.
Gareth Berry
Gareth works closely with clients from the earliest stages of a project, providing strategic direction and technical oversight to lay the foundations for successful GSHP delivery.
Ian Irish
Ian oversees project delivery, ensuring drilling operations are planned, coordinated and executed to the high standards that Onsen is known for.
Mike Ashton
Mike manages our drilling operations on site, working closely with project teams to deliver complex borehole installations safely efficiently and to specification.
Eliott Lipscombe
Eliott leads business operations, developing the systems and processes that support a growing team and deliver a consistent experience for every client.
Looking for a ground source partner?
Whether you're at the planning stage or preparing for delivery, our team is here to help.