Bill Watts, Senior Partner at Max Fordham discusses district heating systems in new-build developments
I’ve been on record for some time questioning the wisdom of the almost-mandated installation of District Heating systems in new-build housing developments in London.
Primary amongst my concerns is the lack of data to support claims of their benefit, and hence a lack of evidence to justify their mandated installation.
Last month, smart-payment and energy-efficiency technology company Guru Systems launched their ‘Pinpoint’ heating data analytics package at the Royal Institution of Chartered Surveyors (RICS). The data it measures and collects will help us shine a light into this murky, complex and expensive technology and enrich our understanding of District Heating efficiency.
I’m not writing as a shill for Guru Systems, but the accurate, real-time collection of meaningful data of functioning domestic District Heating is a welcome development.
They have already captured data from scores of legacy systems currently operating. That data has revealed unprecedented information on these complex systems. Although the presenters from Guru Systems would not be drawn on exactly how inefficient the systems were, it’s clear that as a rule they are operating very poorly.
Tim Rotheray from the Association of Decentralised Energy [ADE] spoke to the RICS audience towards the end of the afternoon, pleading for the government to trust them and not regulate. Self-regulation of any industry doesn’t have a famous history. It relies heavily on a good deal of trust. The District Heating industry has presided over, and promoted, the installation of a range of poorly performing systems for a long time. Investing further trust at this point makes me very nervous.
Is the ADE to blame for this? Perhaps not. Businesses will not do something that is expensive – such as a good job – unless there is some compunction or some market force at work. When it comes to District Heating there is no market force at work. One can charge whatever one likes for heat in this anti-competitive environment. What’s more there is no accountability on carbon standards in use. As we have seen with construction standards in buildings, it was only the threat of a simple airtightness test that brought the industry to take this seriously. To its credit, it did. Standards improved, even if the performance gap remains embarrassingly high.
Does anyone actually want District Heating? The government mandates developers to put it in with a view to providing inexpensive and low-carbon heat to meet the nation’s CO2 emission standards. Without reasonable system efficiency, this will not be achieved. To date, there has been scant concern about the performance of any of the systems. Guru Pinpoint, and technology like it, provides a platform to improve performance of these systems to a reasonable standard. However, without some compunction to achieve these standards, I don’t see the industry rushing to adopt them. Presenting alongside Tim Rothersay was Phil Jones, the Chair of the CIBSE Energy Performance group and a professional champion of these systems. He stated that achieving a improvements in the industry was a 10 year project. This is an extraordinarily relaxed rate of progress. Given that district heat has been all but mandated for a decade, this would be 20 years too late. Much damage has already been done and much money has been wasted. If the government is forcing us to spend billions on installing these systems, they should at least attempt to control the quality.
My understanding is that members of our government know the current District Heating model is terrible, but that it is worth it in the “long run”. When is that, exactly? It would be interesting to see the model to identify how long it will take to pay off the additional CO2 we are releasing now with the notional savings from the technologies in the future. Any future scenarios need to take into account the likely losses of these systems.
The government’s chosen tool to direct energy-efficient design is the SAP calculation, which sets ambitiously low limits for the energy related CO2 emissions from a new building. The tool currently directs designers to more or less ignore the losses from district heating systems when calculating their building’s performance. This is a gift to the industry, whose installations could double the heating energy consumption and CO2 emissions. If the SAP calculations were amended to require designers to be as careful with these systems as they might be with, say, making sure it’s warm enough in winter, that would be a great advance in getting a true picture of installation performance. I understand that the SAP calculation is up for review. However, even if the SAP calculations were 100% accurate – even if they do generate better designs – it will not build or run the building. That will be done by humans with many different motivations and pressures. Without adequate enforcement or market pressure, the performance of the systems installed will remain expensive and wasteful.
Bill Watts
Senior Partner
Max Fordham
https://twitter.com/MaxFordhamLLP
This is an excellent piece, but only addresses the design and build of new systems. We have had first hand experience in London and Bucharest on old district heating systems. For the long-term efficiency of any heating system it is essential to install and maintain water treatment. Corrosion and biofilm in the closed heated Primary water side and calcium carbonate on the Secondary heated water side will greatly inhibit heat transfer in the heat exchangers, resulting in mega energy wastage. Now that effective non-chemical, non-invasive treatment systems can address these issues it is imperative that it is considered at design and refurbishment occasions.
The same can be said about what seems to be the mandated specification of the ‘single point of treatment’ permanent magnet water conditioners. In my experience, large carrier systems, such as district heating, need a multi-point approach with regard to treatment. John is right to raise the issue. Corrosion and biofilm in a primary heating circuit are five, yes five, times less efficient at transferring heat than their counterpart, limescale, is on the secondary side. In other ‘green’ initiatives, such as anaerobic digestion, these issues are now coming to the fore, as efficiency of AD plants reduces due to the fouling of heat exchangers. We need to be more proactive at the design stage rather than waiting for things to fail as we continue to be more reactive on the maintenance and repair side.!