Cambridge's Robinson College leads the way in revolutionary self-sufficient heating

An alumnus of Robinson College in Cambridge, who now runs his own cleantech company, has come up with a revolutionary new way of providing self-sufficient heating as well as helping the local eel population to survive in a tributary of the nearby River Cam.

Mark Hewitt, 56, developed a way of harnessing water from a brook running through the gardens to heat the entire college.

Mr Hewitt, who studied architecture at Robinson College in the 1980s, is the CEO of ICAX, a leading cleantech delivery and innovation company providing renewable heating and cooling for buildings and infrastructure.

He said: “Every year students call alumni to keep them in touch with college news and ask if there are ways we can support the college.

“During the call a couple of summers ago it occurred to me that I could look at the heating system, and see if we could introduce heat pumps for heating and take out some of the gas usage. My room in the college was over Bin Brook, so I guess I was wondering whether this might be a useful source of energy that we could harness. It is a completely sustainable heating source.”

It led to the development of a 300 kilowatt system that extracts heat from the water in Bin Brook, a tributary of the Cam, to support the main boiler system. It is estimated that the cost will be recouped in six years and it will benefit the college to the tune of £1.4million over the next two decades.

It was a timely move, as in his Spring Statement last week, Chancellor Philip Hammond announced that gas boilers will be replaced by low-carbon heating systems in all new homes built after 2025 in an attempt to tackle the escalating climate crisis. New properties would use alternative systems, such as heat pumps, to help the UK reduce its carbon emissions.

But a spin-off from Mark’s work has been the building of the first weir in the country for 10 years.

The Environment Agency was particularly impressed by its design which facilitates the passage of eels up Bin Brook via an ‘eel bridge’.

Mark is now keen to track the progress of the eels.

He said: “We really want to know if the eels will thrive now that we have made a route for them to travel up and down Bin Brook, so we would be grateful to hear of any sightings as people travel past the weir on the way to lunch.

“It is a positive wildlife benefit. It is tragic what has happened to the number of eels in recent years. Bin Brook has a lot of potential as a useful part of the network for the River Cam system.

“It is really exciting. I don’t know of any way of counting eels, perhaps we should launch a competition for someone to design an eel counter.

“Eels are in so much trouble that anything that can help is tremendous.”

Mr Hewitt also believes this could be the start of something bigger across Cambridge.

He said: “Any other colleges that have river frontage can follow Robinson’s lead, and the net impact on Cambridge’s carbon footprint could become quite significant.”

Robinson is one of the newest colleges in the University of Cambridge.

It was founded with a donation by the entrepreneur and philanthropist Sir David Robinson and formally opened in 1981.

It has 80 fellows and around 400 undergraduate and 200 graduate students.