Key People


Toby Heysham

Managing Director

Toby worked in land mine clearance for Halo Trust before moving to work in finance at the Bank of New York Mellon. He left to join the Carbon Census as head of operations. He then co-founded Nova Power and subsequently Pinnacle Power.

Toby has extensive experience in delivering heat based district energy and has worked on projects from 100kW to 87 MW of heat generating plant.  He focuses on working with councils and developers to deliver the most innovative solution possible both financially and practically.


David Paterson

Finance Director

David is a chartered accountant and experienced energy financial modeller, developer and project manager.

Prior to joining Pinnacle Power, David qualified as a chartered accountant with Smith and Williamson. During this time he maintained an active interest in the energy industry and post qualification became an independent energy consultant preparing financial models for new wind, solar and anaerobic digestion projects across the UK.

David spent several years working at Inazin Power limited, where he built built a developable pipeline of >120MW of onshore wind and >60MW of large scale solar sites in the UK.

Jim Birse Pinnacle Power

Jim Birse

Commercial Director

Jim joined Pinnacle in early 2016 to lead the Commercial management of the business and to further develop Pinnacle’s expertise and capacity to deliver substantial district heating and low carbon energy projects.

Jim has 20 years’ experience developing and delivering renewable energy and heat networks projects from design and build through to long term operation and energy services; working both directly with end customers and in a construction contracting context.

Following an early spell running the UK’s biomass renewable energy association, Jim was a founding Director and owner of Econergy limited which grew to become one of the UK’s leading biomass and district heating businesses. Following investment from and ultimately sale of Econergy to British Gas Jim stayed on at British Gas Heat Networks for four years to develop British Gas’ district heating and energy management services.


Peter Mildenstein

Director of Engineering

Peter joined Pinnacle Power in early 2015 to take on the responsibility of developing and growing an engineering team that will bring all the key skills into the business.

Immediately prior to joining Pinnacle Power, Peter spent nearly 6 years at Ramboll UK designing energy systems including energy centres and district heating systems. During his time at Ramboll Peter focussed on detailed design, energy recovery, due diligence, installation and commissioning.

Peter graduated from University in Building Services Engineering and was an early pioneer of district heating through his 15 year tenure with Sheffield’s pioneering district heating system. Peter joined the fledgling Sheffield Heat and Power in 1994 as a technical engineer, combining a hands on operational role, interspersed with designing and installing the expanding scheme. Following Sheffield Heat and Power’s acquisition by Veolia in 2001, Peter took day-to-day control of the business management in addition to the operation and engineering aspects of the building.