The Badger Meter range of innovative water-quality solutions helps our clients from across the globe to safeguard water quality, for the protection of people and processes. Our class-leading water-quality portfolio provides actionable intelligence for the control, management and optimisation of facilities for water safety and sustainability.

As world leaders in smart water quality, disinfection monitoring and control, Badger Meter provides pioneering smart-sensor solutions for HVAC systems.

Continuous monitoring of water quality within HVAC systems plays a vital role in ensuring the long-term health and longevity of building networks, avoiding costly repairs, replacement or downtime. Fluctuations in pressure, pH and conductivity could indicate a leak or burst, or can suggest an issue with the chemistry of the water, where the additives added to kill bugs and germs have become compromised. Monitoring safe levels of dissolved oxygen also helps to maintain system health and prevents corrosion.

Even small changes in these water-quality parameters can, over time, lead to the deterioration of the HVAC system, which, if left unidentified, will require large-scale repair or replacement. Proactively identifying changes at an early stage helps to remove the risk of corrosion, while also, potentially, avoiding health issues such as outbreaks of legionella.

The unique ATi HVAC MetriNet solution from Badger Meter is one of the only monitoring instruments that can detect these subtle changes ahead of time, preventing long-term and costly damage. Flexibility is key with this class-leading system, with its modular nature allowing unique monitoring solutions tailored for individual site requirements.

At the heart of this MetriNet solution are the industry-leading digital M-Node sensors, which are connected to the water supply using a purpose-designed ‘click-connect’ flow-cell arrangement. Through the provision of live, continuous data, the HVAC MetriNet provides a constant health check and is key to protecting the lifespan of the HVAC system and the future of the building.

Discover more about some of ATi’s HVAC MetriNet installations and how the ultra-low-powered, smart digital sensor technology offers sustainable solutions, delivering proactive management to safeguard water quality and system optimisation in a variety of applications: Removing the Risk of Corrosion in HVAC Systems

Dissolved hydrogen sulfide (H₂S) monitoring in geothermal power plants and district heating networks

H₂S monitoring is crucial within geothermal power plants to ensure the safety of workers and nearby communities, and to protect the air, water, soil and vegetation in the surrounding environment.

Geothermal energy is generated by tapping into the heat stored beneath the Earth’s surface and is most prolific in areas of high volcanic activity, or where there are high levels of underground sulfur deposits.  Although it is a relatively clean and renewable energy source, high amounts of H₂S can be released throughout the process, which causes concern because of the potential toxicity and unpleasant odour.

Geothermal energy production in the Reykjavik area of Iceland continues to increase and the Department of Environment for Reykjavik city has been measuring H₂S since 2006, with levels expected to remain below 50 micrograms per cubic metre.

To ensure that the levels of H₂S comply with guidelines and remain within the required levels, managers at a leading geothermal power plant turned to Badger Meter for a class-leading solution.

Developed on one of Iceland’s largest high-temperature geothermal fields, this extensive site is one of the world’s foremost geothermal power plants, producing and supplying electricity and hot water for the district heating networks to Reykjavik.

As a global leader in water-quality monitoring, Badger Meter was delighted to be able to recommend the ATi Q46S/81 Dissolved Sulfide Autochem monitor. This state-of-the-art system continually measures the amounts of H₂S within the district heating water, offering peace of mind and ensuring health, safety and wellbeing for plant personnel and the people of Reykjavik, while also protecting and maintaining the natural beauty of the surrounding area for future generations.

Dissolved Sulfide Monitoring.

The post Intelligent solutions for safer water systems appeared first on CIBSE Journal.

F-gases in refrigerants are known contributors to global warming, and the EU F-gas Regulation 2024/573, which came into force on 11 March, aims to further curb the use of refrigerants with high GWP. The regulation mandates that, from 2027, chiller, air conditioning and heat pump systems under 12kW must have GWP limits of 150, and, by 2032, there will be a full F-gas ban in these systems. From 2027, larger split systems and chillers must have a GWP below 750.

This is part of wider plans to end the use of F-gas, with the EU parliament voting in January to phase-out HFCs, which make up 90% of F-gases, by 2050. This will be enforced by the reduction in HFC quotas set out in the revision of F-Gas III (EU) 517/2014. From 2025, the quotas allocated for HFCs by the European Commission will lead to a reduction of 22% compared with 2024, rising to 12% from 2036. This will result in price rises for remaining refrigerant, which the EU hopes will incentivise a move to low-GWP systems.

The UK is currently drafting its own legislation to align with these rules. It is expected to publish a stakeholders’ consultation document this summer, with a draft regulation published in the autumn.

The Net Zero Carbon Buildings Standard (NZCBS), due in the autumn, will also place limits on the GWP of refrigerants used. A consultation proposed a maximum GWP of 675, which is the GWP of R32, a common refrigerant. It also proposes that refrigerants be accounted for within embodied carbon calculations.

The regulations are driving demand for systems using natural refrigerants, such as ammonia, propane and carbon dioxide, which have near-zero GWP. This is the experience of Edoardo de Pantz, managing director at Acquaria, which manufactures propane (R290) heat pumps and chillers. ‘The market is running faster than the regulations are. The whole supply chain is asking for near-zero GWP heat pumps,’ he says.

BESA technical director and Institute of Refrigeration president Graeme Fox says the upcoming ban on high-GWP refrigerants has led to a sharp uptick in propane systems.

Propane has higher flammability than higher-GWP refrigerants, with an A3 safety classing, and Fox says installers will need to upskill to work safely with the refrigerant.

The EU F-gas regulations state that installers will need a refresher course within five years of the implementation date of the latest regulations (April 2029), and every seven years thereafter. But Fox notes that small systems with a GWP of more than 150 will be banned within three years – before the date when installers have to complete the course. He says manufacturers may stop supplying higher-GWP equipment, even before the implementation date

‘Technicians could be installing highly flammable refrigerants before they’ve had the necessary training, which is very much a concern to the industry,’ says Fox.

In response to the lack of awareness around propane, BESA has published a technical bulletin on R290 in air conditioning equipment and its practical application. Fox says R290 air-to-water monobloc heat pumps designed for housing need special consideration. The refrigerant’s flammability means it must be more than 1.5 metres from an openable window or door, according to manufacturers, says Fox, and because it is heavier than air, it must be more than 1.5m from air bricks and downpipes, to prevent leaking propane from infiltrating the house.

‘In most houses, you’re going to really struggle to get anywhere near the outside of that house and avoid an air brick by 1.5 metres either side of the unit,’ says Fox.

There are also implications for the retrofit of split air conditioning heat pumps in retail outlets or office applications, he adds. A typical application in these sectors is a grid of R407c condensers placed about 300mm apart, perhaps on a gable end. Currently, if one unit fails it can be replaced a similar unit, which is fairly straightforward.

However, it would be impossible to swap in a propane unit, because older units use A1-rated refrigerant that does not require Atex-rated electrical equipment, such as fan motors and electrical meters, so the neighbouring unit is a potential ignition source. (Atex is the name given to the two European directives for controlling explosive atmospheres.) ‘There are very serious implications for retrofit and retrospective repair work with the location of these new units,’ says Fox.

The issue can no longer be left to the AC contractor, he adds, because – under the Building Safety Act – the principal designer has to take responsibility: ‘They have to be aware of it.’

Currently, the European standard BS EN378 governs the safety and environmental standards of air conditioning, refrigeration, chillers, and heat pump systems, and this can be used with three EN60335 product standards that provide more specification details. Several CIBSE guides refer to BS EN378, including AM17 and Commissioning Code R, Guide B and Guide B3. A new version of the European standard is expected later this year (see page 13 to find out more about EN378).

An area Fox believes the EU has overlooked is the application of systems in airports, railway stations and military bases, where flammable A3 refrigerants cannot be used because of the danger of ignition – via sparks from trains and tracks, for example.

‘The EU has a line in the regulations that says higher-GWP refrigerants, such as 410a, can be used if safety standards don’t allow A3 refrigerants, but there’s no point having the exemption if you can’t get the equipment because the quota for these refrigerants is reducing so quickly,’ he says. ‘There needs to be a mechanism to bypass the quota and supply that equipment in these locations.’

For propane chillers, Fox says that – in addition to leak detection and good ventilation – the designer would have to ensure that fans, leak detectors, lights, switches and any power points are Atex-rated.

He is hopeful that issues identified with the latest F-gas regulation will be fed back into the UK’s upcoming consultation document.

‘Just because something is technically feasible doesn’t mean it’s practically applicable,’ he says. ‘We have to be aware of the nuanced application issues that engineers have on the ground.’ 

The post Safe and practical applications: natural refrigerants appeared first on CIBSE Journal.

As well as being a primary driver of climate change, cities are exposed to its negative consequences, and will have to adapt to extreme weather events, such as heatwaves and flooding. The vulnerable will be hit the hardest if society does not adapt to the changing climate. 

One of the greatest environmental risks to our health is ambient (outdoor) air pollution, which leads to increased levels of heart disease, lung cancer and premature deaths. Almost everyone lives in environments exceeding World Health Organization (WHO) guidelines³, and some of our children are exposed to pollution levels that lead to reduced lung capacity and lifelong breathing disorders⁴.

Air quality, and its effects, may also be affected by a changing climate.  It’s imperative that all routes to improving air quality should form part of a wider urban adaptation strategy.

In 2022, the UK Urban Environmental Quality (UKUEQ) partnership was established by the CIBSE Resilient Cities Group and UK Wind Engineering Society. Its aim was to help cities adapt to climate change by gaining a better insight into the urban environment – including air quality –  through the use of urban physics and digital tools such as computational fluid dynamics. UKUEQ now consists of more than 20 organisations from industry and academia.

Some of the key factors determining the quality of the environment include wind, air quality, thermal conditions and acoustics (see panel). Urban physics is about understanding how the ingredients of this urban soup interrelate and are affected by other elements, such as light, water, surfaces, drainage systems and the urban form (morphology), which alters the natural exchanges of energy and water between the surface and air. Ultimately, the multiple factors influencing the urban environment drive the resulting conditions within designers’ models. (See Figure 1.)

For example, as air speeds near the surface increase, more surface heat is exchanged with the air through convection. Conversely, at lower air speeds, more surface heat is exchanged with the surrounding surfaces and sky through radiation. It is therefore important to take wind and urban morphology into account when looking to improve thermal and air quality environments.

Unfortunately, our industry’s design disciplines tend to work in isolation, with little communication at the engineering level. There is a need for increasing collaboration and integration to improve safety and performance, and future-proof our cities.

Early design discussions that consider urban physics can lead to significant gains for the environment. The impact of decisions should be assessed during the various design development stages.

Knowledge gaps remain significant, impeding all practitioners’ ability to enhance societal resilience and address poor environmental, energy and health issues. So, what is being done to fill knowledge gaps?

To increase resilience, more research and development is needed to improve methods, technology, and overall sustainability⁵. Currently, as a building industry, we still experience failures and poor performance when we engage with new technology.

Overall, there is much to do to bring all aspects into a collaborative and integrated approach to solve the problems of the future urban environment. 

• The UKUEQ is a working group of the CIBSE Resilient Cities Group. It will be hosting mini-symposia at the University of Birmingham and University of Southampton this year, and will again be hosting a seminar at CIBSE Build2Perform Live, taking place at London ExCeL from 13-14 November.
• For more details on UKUEQ and its activities, see www.cibse.org/ukueq where you can access the full length version of this article

About the authors
Darren Woolf, chair of UKUEQ and the CIBSE Building Simulation Group, George Adams FCIBSE, CIBSE past president, and Stefano Cammelli, chair of the UK Wind Engineering Society

The authors would like to thank Ben Marner, at Air Quality Consultants, and Blaise Kelly, at TNO, for their contributions to the air quality sections.

References:

1. Zhao et al (2022). A global dataset of annual urban extents (1992–2020) from harmonized nighttime lights, Earth Syst. Sci. Data, 14, 517–534. DOI:10.5194/essd- 14-517-2022
2. Luqman et al (2023). On the impact of urbanisation on CO2 emissions. Urban Sustain 3, 6. DOI:10.1038/s42949-023-00084-2
3. WHO (2022). Ambient (outdoor) air pollution fact sheet.
4. Kings College London (2018). Air pollution restricting children’s lung development. https://www.kcl.ac.uk/news/air-pollution-restricting-childrens-lung-development
5. Alexander Clifford (2023). Understanding the role of R&D in the construction industry.
6. DEFRA (2016). NO2 fall off with distance calculator.
7. DHSC (2020). Chief Medical Officer’s annual report 2022: air pollution.
8. DEFRA (2022). Report: Non-methane Volatile Organic Compounds in the UK.
9. Mayor of London (2023). Air quality positive (AQP) guidance.
10. Mayor of London (2019). Using green infrastructure to protect people from air pollution.
11. DEFRA (2018). Report: Impacts of vegetation on urban air pollution.
12. DEFRA (2016). Report: Paints and surfaces for the removal of nitrogen oxides.
13. DEFRA (2022). Report: Indoor air quality.
14. Cammelli and Stanfield (2017). Meeting the challenges of planning policy for wind microclimate of high-rise developments in London. Procedia Engineering, Volume 198, 43–51.
15. City of London Corporation (2020). Thermal comfort guidelines for developments in the City of London.
16. Woolf, 2024. Cooking up an urban soup that tastes better. CIBSE Home Counties North West & Anglia Ruskin University seminar ‘Accounting for the urban heat island – Integrating multi-disciplinary perspectives for climate-responsive urbanism’, 18th January.
17. World Health Organization (2018). Environmental noise guidelines for the European region
18. Radicchi et al (2020). Sound and the healthy city. Cities & Health, 5:1-2, 1-13. DOI: 10.1080/23748834.2020.1821980

The post The urban emergency: addressing environmental quality appeared first on CIBSE Journal.

Secondary legislation regulations and guidelines are being used as the working values against which indoor air quality (IAQ) can be assessed.

It can be regulated via health and safety regulations, such as the Control of Substances Hazardous to Health (COSHH) Regulations (2002), to which all places of work have to adhere. Regulation 6(1) of COSHH states that an employer ‘should carry out a suitable and sufficient assessment of the risks to the health of your employees and any other person who may be affected by your work, if they are exposed to substances hazardous to health’. Regulation 10 of COSHH specifies that monitoring is required ‘when measurement is needed to ensure a workplace exposure limit (WEL) or any self-imposed working standard is not exceeded’.

There are legally binding WEL for around 500 substances, listed in HSE EH40/2005. However, WEL only relate to personal (exposure) monitoring of people at work, are calibrated for a healthy working-age adult, and can’t be readily adapted to evaluate or control prolonged, continuous or non-occupational exposure. So, for most office and education settings – and all public and residential buildings – WEL cannot be used to assess building occupant exposure to IAQ.

New buildings, however, are covered by the recently updated Statutory Instrument Building Regulations (2010). Now included in Approved Document F1 is ‘Means of Ventilation’, providing statutory guidance on ventilation requirements to maintain IAQ.

Within Approved Document F1, Appendix B: Performance-based ventilation, average indoor air pollutant guideline values are set for carbon monoxide (CO), nitrogen dioxide (NO₂), formaldehyde, total volatile organic compounds (TVOC) and ozone (O₃), largely based on World Health Organization (WHO) guidelines. However, as the document relates to building performance guidance, these values are performance criteria of the assessment of ventilation, not occupant exposure assessment criteria.

For several years, regulations, standards and guidance on IAQ for school buildings have been set out in the UK government’s Education and Skills Funding Agency Building Bulletin BB101. This includes guidelines on ventilation, such as setting a maximum CO₂ in teaching spaces, and specific guidelines on IAQ, mainly based on WHO guidelines that ‘should be used for schools’.

The WHO first published air quality guidelines in 1987, which have been updated since. They ‘serve as a global target for national, regional and city governments to work towards improving their citizens’ health by reducing air pollution’.

In 2010, the WHO published guidance on risks associated with pollutants commonly found in indoor air (benzene, CO, formaldehyde, naphthalene, NO₂, polycyclic aromatic hydrocarbons, radon, trichloroethylene and tetrachloroethylene), and updated their (general) air quality guidelines in 2021 (see Table 1).

It should be noted that WHO general air quality guideline values ‘do not differentiate between indoor and outdoor exposure’, so they are applicable indoors. Some of the latest 2021 guidelines supersede its specific 2010 IAQ guidelines (eg, for CO and NO₂).

They are relevant in all countries and in all exposure settings where COSHH WEL are not appropriate. Organisations, including CIBSE, point to these guidelines for IAQ monitoring. In recent years, other organisations have published IAQ guidance.

About the author
Oliver Puddle is technical director at DustScanAQ

The post The good, bad and illegal: rules and guidelines for IAQ appeared first on CIBSE Journal.

Maidment is professor of heating and cooling at London South Bank University, and works part-time at the Department for Energy Security and Net Zero (DESNZ) on cooling research associated with the government Mission Innovation project. He reminded the symposium that 2023 was the warmest year ever and that, in the UK, a record temperature of 40.3ºC was reached.

Extreme heat has a much greater impact on those who are disadvantaged, said Maidment; in 2022, it led to 5,017 excess UK deaths among the over-70s. He explained that cooling isn’t just essential for comfort, but has many critical applications in other sectors, such as hospitals, preserving food and medicines, industrial processes, and data centres.

He showed projections from UN Global Cooling Watch that indicate dramatic rises in cooling demand and energy consumption of cooling over the next 25 years. Without action to promote sustainable cooling and adaptation, air conditioning and refrigeration could contribute half a degree to global warming, Maidment said.

Moving south

The symposium was shown how much more energy has been used for cooling in the UK in recent years, with Maidment explaining how the number of cooling degree days for Gatwick has increased to an average of 46 per year over the past four years, compared with 29 for the past 20 years. This is similar to Rouen, in France, meaning the Gatwick climate is moving 50 degrees south each year.

Two of Maidment’s DESNZ colleagues, lead technical energy adviser Melanie Jans-Singh and senior energy adviser André Neto-Bradley, described how buildings in their hometowns of Pau, France, and Porto, Portugal, respectively cope with warmer temperatures. Jans-Singh said nearly all windows had shutters and are wider apart, to allow them to be opened, and Neto-Bradley emphasised how building layouts are designed to minimise solar gain.

Jans-Singh said the UK government has been building up evidence on which to base future cooling strategy, and she shared a study on three cooling scenarios for a 4°C temperature rise by 2100. With no policy interventions, energy demand would quadruple and consumption double. The two other scenarios were if the government pursued a passive-first policy or increased use of efficient technologies. Each of these scenarios was costed: no intervention would cost £60bn, passive first £30bn, and more efficient technologies £75bn.

A mix of passive and active solutions would be required, said Jans-Singh, who went on to describe the Global Cooling Prize. This partnership between the UK government and the Rocky Mountain Institute encourages the development of more efficient air conditioning and some recipients have developed systems that are 10 times more efficient than current ones.

Global Cooling Pledge

Maidment spoke about the CSNow project, looking at the energy consumption and emissions from cooling in the UK in 2021. It found that 15% of all electricity is used for cooling, very close to a figure for Germany that was calculated for 2017. The per capita amount of kWh going into cooling for both countries for those years was near identical at 789/790. The full report will be published soon, said Maidment.

Adaptation will be key to mitigating the risks of a warming climate, added Neto-Bradley, and the UK Climate Change Committee has highlighted as a priority the risks to health from overheating buildings. He said the cooling team is working to support evidence-based action to address these risks, and gave details of the Global Cooling Pledge signed by 60 countries at COP28 last December, when nations committed to – among other things – more energy efficient systems, a phasing out of high global warm potential refrigerants, promoting passive-first approaches, and collaborating on innovation and research.

Unified outlook

Maidment ended the keynote by describing how the UK government is meeting one of its pledges to produce a strategic overview of cooling. It will take a sector-by-sector approach to gathering evidence and he is keen for CIBSE Members to join the initiative.

‘This unified outlook will be a chance to identify gaps and opportunities for sustainable cooling,’ he said. ‘We need to be fit for 2050 and beyond – and, to do that, we need a clearer plan of what we’re doing in the UK on cooling.’

The post Sustainable cooling in a warming world appeared first on CIBSE Journal.

Thorough research and testing of the Diffusion Highline 235 modular fan coil range has resulted in a product that considers whole life costing through the use of TM65 and local sourcing to reduce transport miles, the judges added. Energy, acoustics, performance, and the flexibility modularisation brings to deployment and onsite repairs have also been considered.

Working closely with customers, Diffusion researched every UK fan coil on the market to assess how it could improve the design to meet the changing needs of the industry.

As a result, its Highline range has been increased to eight, the modularity of which now allows almost 300,000 configurations. This means customers can select a unit that exactly matches their performance requirements rather than having to over-specify, ensuring the lowest energy consumption.

At design stage, the emphasis was on using fewer materials, reducing the volume of materials transported, minimising carbon footprint, and lowering running costs per unit size.

Leveraging high-efficiency EC/DC motor and fan assemblies, the units achieve a specific fan power as low as 0.14W.L^-1.s^-1, significantly reducing energy consumption and operational costs. Forward-curved centrifugal fans provide the most efficient airflow and acoustic performance in all models. Further acoustic benefits are achieved through ‘0’ fire-rated foam insulation.

The unit’s heat exchangers are manufactured from solid drawn copper tubes, mechanically expanded into pre-formed collars in rippled plate aluminium fins. Multi-circuit design ensures maximum thermal performance. For optimum heat transfer into the airflow, electrical elements are 8mm-diameter, fully sheathed, stainless-steel rods, with spiral-wound fins.

Highline 235 is supplied with Diffusion’s Lifetime Eco wire-mesh filter, which can be simply vacuum cleaned in situ. It lasts the lifespan of the unit. 

ISO-grade media filters are also available. When filters need to be cleaned or replaced, they can be easily removed from either the side of the unit or from beneath it.

In spaces where noise levels significantly influence occupant satisfaction, the Highline 235 range can achieve noise levels ranging from NR25 to NR40. Discharge plenums are available in rectangular or circular spigots, and inlet and discharge attenuators are available in lengths to meet requirements.

British designed and manufactured with a short supply chain, 70% of Diffusion’s fan coil units (FCUs) are transported less than 24 miles to end users in London, keeping carbon emissions to a minimum. The modular, configurable design means building owners can reuse the FCUs by repositioning them.

The CIBSE TM65 data-collection methodology was used to collect accurate and detailed embodied carbon information about the system. Working from a component level, this methodology ensures data is comprehensive and up to date.

Diffusion uses its in-house test facility to offer volumetric, acoustic and thermal performance testing, and customers can watch their chosen products being tested and certified. They can also input their building’s design parameters into Diffusion’s software to select the ideal FCU for their required temperature and flowrate. This includes data on correct heat exchanger selection.

The judges said the range of innovations among award entries this year showed that innovation doesn’t need to be ‘epic’ to be influential and beneficial. They also illustrated the importance of product testing.  

• For more on the winners at the CIBSE Building Performance Awards, visit www.cibse.org/bpa

The post High fives for Highline 235: CIBSE award-winning fan coil unit appeared first on CIBSE Journal.

The rollout of heat pumps powered by low carbon electricity is a central feature of climate change policies in many countries, including the UK, usually with an emphasis on their use in dwellings. Much less attention has been paid to non-domestic buildings, though their aggregate energy consumption for space and water heating is comparable with that in dwellings, and non-domestic heating makes up 30% of all heating systems in the UK.

To encourage the uptake of heat pumps in these buildings, an ongoing UK-led International Energy Agency (IEA) project, Developing the market for retrofitting heat pumps to non-domestic buildings, is looking at providing tools and guidance for building owners and managers of non-domestic buildings. Following a review of literature in the sector, the project felt that there was a particular gap in guidance for building owners, whereas building service engineers are partially catered for by CIBSE AM17: Heat pumps for large non-domestic buildings, one of the few documents on heat pumps in non-domestic buildings.

The project – headed by the Department for Energy Security and Net Zero, alongside organisations in Austria, Canada, Ireland, Italy, and the Netherlands – aims to address the gap in high-level guidance for non-specialists, and collate and share exemplar case studies.

An interactive tool is being developed that will ask users about their existing buildings and systems, and their principal objectives and constraints, before offering them a shortlist of possible system types.

The tool interface will guide users towards the options that appear to be most promising; these can then be evaluated in more detail, using expert advice as necessary. Their shortlist will be linked to generic descriptions of the relevant system types and their principal characteristics, and to two-page summaries of case studies in buildings that resemble their own.

The most suitable choice for a retrofit heat pump system depends on a complicated interplay between: the size, use and complexity of the existing building and its heating system(s); the range of heat pump system options that are possible; and the priorities and concerns of the building owner.

It is likely, especially for smaller organisations, that initial decisions around replacing heating systems will fall to individuals who are not experienced in navigating this maze. At the current low levels of market penetration, they are also unlikely to be familiar with existing heat pump installations. These are the individuals and organisations that this project aims to help.

The decision-support tool will need to map a large number of possible system configurations against the information provided by a tool user. Its basic logic structure – which has been agreed and is now being developed – has three stages that progressively reduce the number of options being considered (see Table 1).

Initially, the tool identifies constraints that limit the range of practicable options; then it focuses on those that are compatible with the existing heat-distribution system; and, finally, it produces the shortlist of options that best match the priorities identified by the tool user.

In most cases, it is expected that the initial two stages will reduce the number of feasible options to a manageable number that can be ranked according to the priorities of the tool user. The third ranking stage requires a set of comparative costs and seasonal efficiencies, such as would be used during design evaluations.

It is expected that tool users will have varied backgrounds, priorities and levels of prior knowledge, reflecting the multiple and sometimes complex procurement procedures that could be used for various levels of retrofit and type of organisation. Guidance will need to be accessible and relevant to, and understandable by, a wide range of ‘decision influencers’.

Exemplar case studies

More than 70 case studies have been identified across the participating countries (including a few in other countries). About 25% are in the UK and are predominantly public sector buildings supported by the Public Sector Decarbonisation Scheme (for which measured performance data is not yet available). In the UK, the projects are predominantly air source heat pumps, often bivalent or high-temperature.

Case studies illustrate the practical application of particular combinations of systems and buildings. With sufficient measured data, they can also provide evidence of performance in use. As the portfolio of case studies grows, the guidance provided by the tool will be compared with systems that were actually selected, which will provide an indication of whether this logic needs modifying.

Preliminary comparative ratings have been carried out on the UK case studies to assess the heat pump types with the lowest capital cost, highest carbon savings and highest carbon savings per £ of capital expenditure (capex). See Figure 1. 

• We are keen to collect information from building owners, facilities managers, system designers and contractors who have already been involved in retrofitting heat pumps in non-domestic buildings, or who are thinking about a retrofit. Contact roger.hitchin@hotmail.com
• The project website is: heatpumpingtechnologies.org/annex60

The post The bigger picture: non-domestic heat pump retrofits appeared first on CIBSE Journal.

Regulations will require minimum technical standards, under a Heat Network Technical Assurance Scheme (HNTAS), for all new-build heat networks from 2025, including the 50,000 residential connections already happening each year. This could rise to 100,000 heat interface units being installed annually in the foreseeable future, partially driven by the regulations themselves.

All 14,000 existing (legacy) heat networks will also be covered, including the 500,000 residential customers currently supplied by heat networks. However, the number of networks is probably a significant underestimate, and improved data could easily indicate there are more like 18,000 legacy networks.

Both communal and district heat networks will be included in the regulations, with the majority of legacy networks being relatively small, communal (single block) networks. The regulations will recognise that many of these communal systems are old and not in the best state of repair, often resulting in poor performance and customer outcomes.

HNTAS is addressing how we can bring these up to a reasonable performance standard over a reasonable period of time. The technical standards will be outcomes-based, so networks will need to meet key performance indicators (KPIs) to gain Heat Network Certification.

For the past 18 months, the Department for Energy Security and Net Zero (DESNZ) has been developing HNTAS, building on CP1 (2020). The work has been led by technical author FairHeat, in partnership with Gemserv, which is focusing on procedural aspects of the assurance scheme.

HNTAS is proposing that a single ‘responsible person’ be accountable for each heat network

Normative documents have now been developed, setting out the necessary governance, structures, procedures and technical standards required to ensure a minimum level of performance and reliability for heat networks.

HNTAS core principles are that the scheme will be outcomes-orientated, preventative, proportionate, deliverable, adaptable, and enforceable. See ‘Assuring quality of heat networks’, CIBSE Journal, May 2023.

The technical normative documents set out clear and measurable KPIs (technical minimum requirements) to be met for each element of a network, plus the evidence required and depth of assessment, along with ‘key failures’ that need to be avoided.

Draft normative documents have been developed in collaboration with sector stakeholders through an extensive series of technical sub-working groups. This involved 25 technical sub-workshops, bringing together 69 stakeholders from 44 diverse organisations, including manufacturers, housing associations, local authorities, consultancies, developers, contractors, energy service companies, trade associations, and professional bodies. This industry engagement will continue with a HNTAS consultation in the summer.

HNTAS’s proposed approach is to certify individual heat networks. Our work-in-progress model is shown in Figure 1. It combines a series of assessment gateways (orange) that, ultimately, lead to certification (blue). Most of the detailed technical assessment work, carried out by registered and trained assessors, will take place across the orange stages, with the clipboards showing assessment points, and the dotted lines as gateways to proceed to the next stage.

The normative documents set out the detailed minimum requirements at each assessment through design, construction and commissioning. These design/construct/commissioning gateways aim to ensure the network is likely to meet future operational performance targets and gain full certification. There is a clear requirement to have binary yes/no decisions, with certification (authorisation to supply heat to customers) awarded to networks that meet minimum technical requirements. By requiring responsible persons to demonstrate that their heat network performance meets KPI thresholds, before allowing a network to pass through each assessment gateway, the scheme is ‘preventative’ and ‘outcomes-based’ (two of the core principles of HNTAS).

This approach aims to ensure that the great majority of heat networks pass at the point of certification, and that key failures in the market are avoided. There are 28 KPIs, categorised into six categories, that set a framework for measuring and monitoring heat network performance. The six categories are: energy centre; district distribution network; thermal substation; communal distribution network; consumer connection; and consumer heat system.

Existing legacy networks will, inevitably, find it harder to meet the HNTAS minimum standards than new networks. So, HNTAS is taking a pragmatic transitionary approach to bring legacy networks as close to full standard as possible, as soon as possible. HNTAS will set out a transition period, during which improvement plans will need to be submitted and minimum levels of metering will need to be installed. Once metering is in place, networks will be in a position to evidence-measure performance accurately and move to full certification.

Fixing legacy networks

For legacy networks, HNTAS aims to ensure the market is able to comply and that the very worst-performing networks are addressed early. To achieve a steady improvement in performance over time, the goal is for every network to be fully certified to a minimum level of performance by a set future date. The proposal for legacy networks is a two-stage transitional approach, which will require minimum levels of metering and monitoring to be installed, followed by the need to report performance, with a minimum threshold that all heat networks must meet within a set period.

Operators will be required to submit a Heat Network Improvement Plan, setting out how they will achieve certification within a set period following the installation of metering, and will need to prove in-use performance after two years of operation, based on real data. It is proposed that networks installed before 2015 will be allowed more relaxed targets than those installed post-2015, when the Heat Networks (Metering and Billing) Regulations came into force.

HNTAS is proposing that a single ‘responsible person’ – such as the owner or developer – be accountable for each heat network. Duty holders of the designated designer, contractor and heat network operator are accountable to the overall responsible person for the day-to-day running of each project stage. This designation of duty-holder responsibilities is similar to the requirements in the Building Safety Act.

The project team is keen to ensure that this is a deliverable scheme, which is proportionate and does not place too much burden or cost on heat network operators or consumers.

During the operational stage, if the network achieves HNTAS minimum performance standards it moves into a stage where the heat network operator regularly submits data to the HNTAS portal (currently being developed), to show that it is still meeting the HNTAS KPIs.

More detailed assessments are only triggered where it falls outside the KPIs. Essentially, this allows a level of ongoing self-assessment for networks that meet minimum performance levels.

Evidence and data requirements will form a ‘golden thread’ throughout all stages of a network’s life, requiring submission of data into the HNTAS and Ofgem digital platforms. It is hoped much of this data submission will be automated, to minimise time and cost.

It is clear that significant change is coming in 2025 as the sector transitions to a regulated heat network market, and setting minimum technical standards is a key part of this. Assessing and certifying heat networks that meet the minimum standards will raise sector performance.

HNTAS is moving into a pilot phase across 2024, to test that it works in practice on real networks, before final implementation in 2025. Engagement with stakeholders throughout this process will continue, as this is key to achieving sector buy-in for the assurance scheme.

There are significant benefits and opportunities that will come from HNTAS: a commercial market for trained and registered assessor services; a general improvement in heat network performance, with consumers seeing improved reliability and service levels; social landlords and local authorities being able to provide more affordable heat; and investors viewing networks as more investable.

There is still a great deal to do to develop heat network regulations, through consultations and secondary legislation. DESNZ aims to publish the HNTAS normative documents in some form this year. HNTAS piloting will take place throughout the year, and DESNZ is seeking heat network operators and assessors that would like to take part. Plans to update CIBSE CP1 are also being put in place, to ensure alignment before regulations are implemented in 2025. A methodology to calculate the carbon content of heat should also be in place by that date.

Heat networks are complex and introducing regulation is not straightforward, so it is important to give this sector early sight of direction of travel. As such, this is a work in progress and does not represent government policy. A DESNZ HNTAS consultation this summer will continue sector engagement, and this work will put in place the missing piece of the heat network jigsaw, namely heat assurance. 

• Based on a paper presented at the 2024 CIBSE Technical Symposium www.cibse.org/symposium

About the authors: 
Professor Phil Jones is an independent consultant working on the DESNZ HNTAS team; Gareth Jones is managing director of FairHeat, the HNTAS technical author

The post Heat networks: countdown to regulation appeared first on CIBSE Journal.

As facility managers are now held more accountable for the overall water and energy consumption of buildings, having access to highly accurate and reliable flow and energy metering technology has become vital. These meters make it possible for facility managers to measure the performance of various HVAC systems and, ultimately, make the best possible decisions to optimize efficiency and manage consumption.

Discover how this global shift towards precision and efficiency has resulted in another successful project using digital flow solutions from Badger Meters. These include no moving parts, zero straight run requirements and digital communication outputs, providing the necessary precision and accuracy needed for hospitals around the world.

How can you improve the quality of medical provision and become more environmentally friendly? This case study demonstrates how a children’s hospital in the U.S. achieved this by selecting the class-leading ModMAG® M2000 Electromagnetic flow meters and Dynasonics® TFX-5000 Ultrasonic Clamp-on flow meters, providing effective management and system optimization.

Enhancing hospital heating and cooling systems

High standards of medical care are essential for the health and well-being of patients and staff. However, not only do the latest medical devices and procedures play an important role in meeting strict requirements, but the quality of indoor air and temperature regulation is also crucial. In older buildings, outdated or inefficient heating and ventilation systems can lead to problems such as mold growth, air pollution, energy waste, overheating or overcooling. These issues can in turn have negative effects on health, hygiene, infection prevention, patient satisfaction and working conditions.

To ensure the most efficient and precise monitoring equipment for heating and cooling systems was installed, the hospital used the latest digital flow solutions from Badger Meter. These solutions offered zero straight run requirements with no moving parts and are able to measure flow and BTU energy across the primary and secondary loop systems, including individual air handlers across the hospital. The hospital decided to use solutions from Badger Meter to provide the necessary precision, choosing direct digital flow measurement rather than relying solely on pressure drop across the chiller pumps.

Hospitals rely on chillers to provide chilled water for cooling and dehumidifying the air in their facilities, but chillers are among the largest energy consumers in hospitals, accounting for up to 40% of the total electricity use. Therefore, improving the efficiency and reliability of chillers can have a significant impact on reducing energy costs and carbon emissions, as well as enhancing patient comfort and safety.

Direct measurement of flow vs. pressure drop across chiller pumps

Direct digital flow measurement is a method of measuring the flow rate of chilled water in a cooling system, using digital flow meters such as the class-leading ModMAG M2000 Electromagnetic flow meters or the Dynasonics TFX-5000 Ultrasonic Clamp-on flow meters from Badger Meter. These devices use electromagnetic or ultrasonic technology to measure the velocity and volume of the water passing through them. They provide real-time data on the flow rate, which can be used to optimize the performance and efficiency of the chillers. In comparison, pressure drop measurement estimates the flow rate of chilled water, based on the difference in pressure between the inlet and outlet of the chiller pumps. However, this method assumes a linear relationship between the pressure drop and the flow rate, which means it may not be as accurate in some cases. Pressure drop measurement may also be affected by other factors, such as pipe friction, valve settings and pump speed.

What are the advantages of using direct digital flow measurement over pressure drop measurement?
First, it allows the chillers to operate within their ideal operating range, maximizing their efficiency and minimizing their energy consumption. Flow-based control can adjust the chiller staging according to the actual flow rate, while pressure-based control may lead to over- or under-staging of the chillers, resulting in less efficient operation and higher energy costs.

Another advantage is that it can help detect and diagnose system problems, such as pump failures, pipe blockages, leaks or air pockets. Digital flow meters can alert the operators of any abnormal flow conditions and help them take corrective actions. Direct digital flow measurement has no moving parts and nothing to wear out or fail over time, resulting in lower maintenance costs. Pressure drop measurement may not be as sensitive to system issues and may not provide enough information to identify the root cause of the problem.

Using direct digital flow measurement can also support efficient load balancing in systems with multiple chillers. Digital flow meters can ensure that each chiller operates at its optimal load, avoiding overloading or underloading of any chiller. This can extend the equipment’s lifespan and reduce maintenance costs. Pressure drop measurement may not be able to achieve the same level of load balancing and redundancy and can get costly when you must stack pressure transmitters.

The flow data gives hospital engineers precise information on how their system is operating and any necessary adjustments operators need to implement to ensure the best possible performance. Alternatively, when using pressure drop across the chillers for measurement data, there are many items that need to be maintained (for example the primary and secondary differential elements like the pressure transmitters). These pressure transmitters, along with their oil-filled impulse lines, can get clogged or leak over time causing the pressure device to fail, losing important control of better staging chiller sequences.

However, the data coming from the digital flow and energy measurement solutions by Badger Meter can be received in the latest communications protocols, including BACnet MS/TP, Modbus RTU, BACnet/IP, Modbus/IP and Modbus TCP/IP. These latest communications will speak directly to a hospitals Building Management System (BMS) for clarity when making important chiller operation decisions. Badger Meter also ensures that our communications technology has been fully tested and certified by industry leading laboratories like BACnet Testing Laboratories (BTL), which will help to ensure startup success when connecting to the hospital’s BMS. Differential pressure solutions must provide an external communications system comprised of multiple vendors and third-party modules just to connect to the hospital’s BMS.

Gaining greater control over hospital HVAC systems

This recent installation showcases the shift towards precision and efficiency in hospital heating and cooling systems globally, utilizing trusted, reliable and accurate technology with no maintenance required. These digital flow solutions from Badger Meter, with zero straight run requirements, offer the latest technology, providing this necessary precision and accuracy for hospitals around the world.

The digitalization of HVAC networks allows for the ability to capture much larger amounts of data from every part of the facility, as well as the integration of different types of intelligent systems. The increase in available data will provide more visibility into facility conditions, expanding the ability for increased automation, along with benefits such as:

• Increased comfort
• Decreased operating cost
• Reduced downtime risk
• Increased safety

Check out the M2000 Inline Electromagnetic and the non-intrusive Ultrasonic TFX-5000 digital flow solutions from Badger Meter to learn more about direct digital flow measurement and the benefits it can offer to your cooling system.

Flow monitoring, water quality sensing and toxic gas detection within hospitals

Flow instrumentation, water quality monitoring and toxic gas detection are all crucial aspects of the management and operation of hospital facilities. The unique and innovative range of solutions from Badger Meter helps to improve efficacy, maintain a safe environment and provide audit trails for regulatory compliance by:

• Maintaining and safeguarding clean, safe and reliable water supplies into healthcare facilities
• Optimising and preventing corrosion within HVAC systems
• Monitoring chlorine levels during renal dialysis
• Validating sterilization cleaning processes by monitoring residual gas levels.

Our expertise in sensor design and manufacturing allows us to deliver the highest level of protection for people and processes within healthcare and pharmaceutical environments.

For more information  on the Ultrasonic Clamp-on flow meters visit Badger Meter

For more information about ModMAG Electromagnetic meters from Badger Meter visit: ModMAG® | Badger Meter

The post The vital role of flow and energy measurement in hospital HVAC systems appeared first on CIBSE Journal.

The HNZ consultation is part of wider changes and proposals, including the December proposals for heat networks in the Future Homes and Buildings Standards (FHS/FBS) and the upcoming regulation of heat by Ofgem. As part of this, the Department for Energy Security and Net Zero (DESNZ) is creating a Heat Network Technical Assurance Scheme, and networks will have to meet its criteria to be allowed to operate.

The current proposals allow for the continuing development of high-carbon networks for years to come, but without doing enough to support their decarbonisation, said CIBSE, which called for the decarbonisation of existing and planned networks to be addressed. It noted that, based on the current data available through the heat metering regulations, 91% of the UK’s 11,847 networks currently use natural gas or oil as their primary fuel. CIBSE also noted that, based on DESNZ data about the pipeline of heat networks, more than 45% of heat network expansions in the pipeline are proposing gas – for boilers or combined heat and power (CHP) – as their primary fuel. However, neither consultation sets out a clear expectation and reasonable timeframe for decarbonisation of heat networks, said CIBSE.

Zoning
The HNZ consultation is significant: in zones identified by a new ‘central authority’ and local zone coordinator, new buildings, existing communally heated buildings, and some existing non-domestic, non-communally heated buildings would have to connect to the heat network. A national zoning methodology would determine which areas are suited to a heat network in terms of value for money and deliverability. It is not clear at this stage how the methodology would assess networks against alternatives, in terms of carbon impacts and costs to consumers. CIBSE does not agree that the main counterfactual to heat network zoning is ‘do nothing’ (as is the case in the heat zoning consultation’s impact assessment), and said there needs to be a focus on other options for heat decarbonisation: ‘This is the real test of whether heat networks offer a cost-effective decarbonisation option,’ it said.

CIBSE is concerned that carbon performance and costs to heat-network consumers did not appear central to the current zoning proposals: for buildings that have to connect to a network, exemptions on grounds of carbon performance and consumer protection are unclear, while they were more prominent in the 2021 consultation, said CIBSE. ‘It is a serious risk to carbon emissions reductions, and to consumers. This must be revisited,’ it said.

CIBSE agrees that building owners should be able to apply for exemptions to connection on grounds of capital cost and timing, but said there must also be exceptions for low carbon buildings. High operational costs for consumers of a heat network must also be a reason for exemption.

Carbon limits
While CIBSE welcomes the fact that networks within a heat zone would have to meet minimum carbon content of heat criteria, it has concerns about the carbon emissions methodology used to demonstrate these criteria, which risks ‘significantly underestimating and misrepresenting the operational carbon impacts of heat networks’.

First, it said the methodology proposes to use a carbon factor for CHP-generated electricity of 304g/kWhe– this is much higher than the current grid average, and is only exceeded by the grid for a small number of hours in the year (eg, around 30-40 hours in 2030, according to data from Carbon Intensity). This means the methodology would attribute benefits to CHP-generated electricity that are unlikely to be realised in practice, and even less so in the future as the Grid continues to decarbonise, said the response.

Second, the methodology does not include secondary losses in the distribution system, which could mean the underestimation of emissions, added CIBSE. While secondary systems are often under different ownership and responsibility, the secondary losses must be accounted for in one way or another, as losses are often significant, contributing to energy waste and overheating in communal parts, said CIBSE. The record of heat networks under the heat metering regulations showed 29% losses  on average, even in communal rather than district networks.

DESNZ should provide a trajectory of carbon limits applying to heat networks, so that networks are encouraged to take early measures before being required to do so, said CIBSE’s response, which also called on government not to wait until the mid-2030s, as proposed, to develop low carbon standards for networks. It proposes standards are created as soon as possible given the significant time lags between planning and operation of heat networks, and would welcome dialogue with DESNZ, as it believes CP1 Heat networks: Code of Practice for the UK could play a role in this.

Public register
CIBSE’s recommendation for the HNZ and the FHS/FBS is to create and maintain a public register of networks, which would be operated by organisations independent from heat networks’ interest. According to CIBSE, this should be publicly available and independently audited, and be the single source of information for any policy relying on operational performance of networks, including Building Regulations, zoning, funding, and so on.

The register should have information currently included in the heat metering register, and have additional data on individual networks – including energy use per fuel – allowing analysis of primary and secondary losses, and carbon content of heat, said CIBSE. It added that this is not the case currently, with the heat metering register providing information on the heat generated and supplied, and on the type of fuel used, but not its amount, preventing an estimate of energy efficiency and carbon content of heat. 

The upcoming regulation of heat by Ofgem creates the perfect opportunity to address this, added the Institution, and it would be happy to discuss this with DESNZ.

The post Heat network zoning: CIBSE response to the recent government consultation appeared first on CIBSE Journal.