By Anthony Harrington
Fife Council has begun work on one of Scotland’s largest district heat networks. The scheme, which has already attracted a great deal of attention and interest, is fairly unique as it utilises the availability of an existing large biomass combined heat and power plant currently owned by RWE.
As Ross Tulloch, programme manager for Glenrothes Energy Network at the Council explains, the opportunity to work towards a district heating network for council buildings began in talks with RWE, who originally installed the biomass boiler for the nearby Tullis Russell paper mill.
“The scheme matured through detailed discussions and feasibility studies over the course of a few years. The council then managed to secure funding for the scheme, which we estimate has total costs in the region of £23.9 million. RWE are in partnership with us on this project, and they have committed £13.573m, which was used to secure repayable assistance of £8.5m from the Scottish Government’s Low Carbon Infrastructure Transition Programme (LCITP), which is co-funded by the European Regional Development Fund” Tulloch comments.
Dr. Mark Picton, RWE site manager for the Markinch CHP plant, points out that the basis for the present district heating system dates back to 2010, when Tullis Russell were unhappy with the efficiency of the coal-fired power plant on the site.
An evaluation of the plant showed that it would need a significant capital spend to upgrade it. So, work began with RWE who built a new, bespoke combined heat and power plant (CHP) capable of providing the quantity of steam Tullis Russell needed for its paper making operation. RWE commissioned the CHP in 2014, just in time for a global slump in the demand for paper.
Tullis Russell ceased paper making operations at the site apart from an offshoot purchased by former employees, known as Glenrothes Paper Ltd, which continues to manufacture specialist insulating paper and receives a small volume of steam necessary for the process.
On March 26th this year Fife Council officially gave the go-ahead for the Glenrothes Energy Network. As Picton explains, RWE’s role in the partnership commits it to building an Energy Centre on the old Tullis Russell site that will receive steam from the CHP plant, convert it to hot water and thereby drive the district heating network.
“We plan to have the Energy Centre in operation by January 2019 and whilst the project won’t generate additional long term jobs, the CHP is already generating significant local employment opportunities. We employ some 40 local people as part of RWE Markinch, and there are a similar number of subcontractors providing services such as security, industrial cleaning and fuel delivery work,” he explains.
The CHP plant burns around 450,000 tonnes of biomass a year, of which around 90% is classified as RCF, or recovered cellulose fibre – waste wood by any other name. The rest is wood from sustainable Scottish forests. All the wood is delivered in the form of wood chip, by a fleet of wagons, which can number up to 70 a day.
There are three local wood processing plants providing wood chips to the RWE site, so the CHP system and the Glenrothes Energy Network could be said to be helping to support still more jobs at those supplier sites.
The Fife Council scheme maximizes the opportunities of obtaining heat from the availability of the existing CHP plant. However, the capital costs for the biomass plant, at some £300m for the complete installation, are just too high for the economics to make sense for most situations. That said, it is recognised that each district heating scheme is unique in terms of geography and socio-economic factors, and the scheme will allow important lessons to be learned as the Scottish government seeks to increase the availability of district heating.
Like all new district heating schemes, the Fife Council one is designed to operate for more than 40 years and in time will be able to distribute heat from more sources than just the RWE biomass plant and Energy Centre.
In the immediate future, there is more than sufficient capacity in the Markinch CHP plant for RWE and Fife Counci l to extend the district heating network to other users in the surrounding area. “We are building the Energy Centre larger than is needed for the initial demand of the Glenrothes project so there will be plenty of scope to extend the heating network to include other users,” Picton says.
“We hope the Fife Council scheme will be a demonstration of what can be achieved with modern district heating,” he says, addings that while the economic case is important, it is not the only rationale for installing a district heating network, and it is easy to imagine situations in which a return on investment, or even break even, would be the determining factor. “We have a number of homes in Scotland that suffer from fuel poverty, some of these are in quite densely populated areas. One of the drivers in a district heating network is to provide affordable low carbon heat for local residents,” he notes. Plus there is clearly a fuel security argument to be made for freeing the UK from any future reliance on natural gas imports. 
Fife Council’s Ross Tulloch explains that the Glenrothes Energy Network is set to be commissioned by December 8th for a demonstration run, with heat being supplied to both Fife House (the Council’s main building) and Glenrothes House by January. “We can already see lots of positive benefits from the project,” he notes. These benefits include reduced energy costs both for the Council and for any industrial and commercial customers that the Council and RWE are able to sign up,” Tulloch says.
He points out that local households who sign up will see reduced maintenance costs on their central heating systems and will have a much lower carbon emissions record for their particular dwelling.  We think the district heating network in Glenrothes is going to help with things like economic regeneration in the area and will be a great demonstrator scheme for the Scottish government,” he comments.