A GUIDE Net Zero Carbon Healthcare - Arup
A GUIDENet ZeroCarbonHealthcare
ContentsNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O N INTRODUCTION AND APPROACH LEAN CLEAN GREENEMBODIED CARBON INTRODUCTION AND APPROACH BUILD NOTHING BUILD LESS BUILD CLEVER MINIMISE WASTECHALLENGING THE NORM
NET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMNet Zeroand the NHSTHE EMISSIONS CHALLENGEBuilding design in the UK faces an unprecedentedchallenge to reduce the impact of construction andoperation on the environment. In June 2019 the UKGovernment passed a law to require the UK to endits contribution to global warming by 2050, with allgreenhouse gases to be net zero by this date. This meanssignificantly reducing the carbon emissions, as well asoffsetting carbon.For its part, the NHS has committed to a ‘Greener NHS’,aiming towards net zero. Many trusts have alreadypublished their sustainability strategies supportinga progression to net zero by 2050 or before.THE INVESTMENT CONTEXTThe healthcare system in the UK is responsible for anestimated 4 to 5% of the country’s carbon footprint1.In 2019, the UK Government pledged to the constructionof 40 new hospitals within the UK. The HealthInfrastructure Plan (HIP)2 capital investment programmeis unprecedented, but also creates significant challengesin aligning with the net zero carbon aspirations.Aside from the HIP building projects, the many existinghealthcare facilities face the challenges of significantmaintenance issues, historic infrastructure and buildings,and a lack of capital. This can make it difficult toimplement changes designed to achieve a /health-infrastructure-plan.pdfin operational emissions.THE RESPONSEThis guide considers an approach to the design of netzero carbon healthcare buildings, providing a frameworkfor building design to have the greatest impact on theembodied and operational carbon. It covers:W H AT N E T Z E R O C A R B O N M E A N SW H AT C O N T R I B U T E ST O O P E R AT I O N A L C A R B O NA N D R E L AT E D C O N S I D E R AT I O N SW H AT C O N T R I B U T E STO EMBODIED CARBONA N D R E L AT E D C O N S I D E R AT I O N SHOW WE CAN CHALLENGE THE NORM3/24CONTENT
NET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHDefining NetZero CarbonAt the time of writing, the UK Green BuildingCouncil (UKGBC), framework3 defined within‘Net Zero Carbon Buildings: A FrameworkDefinition’, published in 2019, is consideredthe most appropriate route for defining zerocarbon in both construction (embodied) andoperation of buildings. The framework, at ahigh level, is as follows:R E D U C E C O N S T R U C T I O N I M PA C T SCritically appraise the potential operationalenergy demands and reduce through a holisticdesign approach.EMBODIED CARBONCHALLENGING THE NORMNet Zero Carbon - ConstructionNet Zero Carbon - Operational EnergyReduce Construction ImpactsA whole life carbon assessment should be undertaken anddisclosed for all construction projects to drive carbon reductions.The embodied carbon impacts from the product and constructionstages should be measured and offset at practical completion.Reduce Operational Energy UseDReductions in energy demand and consumption should beprioritised over all other measures.DIn-use energy consumption should be calculated and publiclydisclosed on an annual basis.Follow a route to reduce construction impacts/embodied carbon.R E D U C E O P E R AT I O N A L E N E R G YO P E R AT I O N A L C A R B O NIncrease Renewable Energy SupplyDOn-site renewable energy source should be prioritised.DOff-site renewables should demonstrate additionalityUSE RENEWABLE ENERGYUse renewable technologies to reduce the carboncreation from remaining operational energy use.3Offset Any Remaining CarbonOFFSET REMAINING CARBONAny remaining carbon should be offset using a recognisedoffsetting framework.Calculate the remaining carbon after all othermeasures, and offset.The amount of offsets used should be publicly o-carbon-buildings-a-framework-definition/UKGBC: Net Zero Carbon Buildings: A framework definition; April 20194/24CONTENT
NET ZERO AND THE NHSDEFINING NET ZEROThe ArupApproachARUP APPROACHO P E R AT I O N A L C A R B O NCHALLENGING THE NORMABILITY TO REDUCEO P E R AT I O N A L C A R B O NTo achieve a net zero building design, theengineering has to be a fundamental part ofthe conversation from the outset of a project.Building design- Orientation & formSpace planningOur approach centres around ensuring that the engineeringstrategies are established early. This maximises theopportunity to reduce the embodied and operationalcarbon of designs.The carbon emissions that can be influenced by designdecisions is shown opposite. As the project progresses, theability to impact overall carbon reduces. In other words,our ability to make significant impacts on operational andembodied carbon diminishes the further into the building’sdesign decisions are made.EMBODIED CARBONSystems design- Efficiency & green technologyPost-occupancy evaluationto tune building systemsBRIEFDESIGNCONSTRUCTIONCOMMISSIONO P E R AT I O NMinimise waste- Good material specificationMaterial & formChallenge space requirements- Grids & spansChallenge brief/performance criteriaABILITY TO REDUCEEMBODIED CARBON5/24CONTENT
CONTENTNET ZERO AND THE NHSOperationalCarbonDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMN H S O P E R AT I O N A L C A R B O N S P L I TOperational carbon is divided into regulatedand unregulated carbon emissions.T R AV E L15-20%Regulated carbon emissions are covered within PartL of UK Building Regulations. Within a healthcaresetting the emissionscan be circa 20% to 25% of theoperational carbon.PROCUREMENT60-70%O P E R AT I O N A L C A R B O N S P L I TThe split of embodied carbon on a non-domesticproject varies depending on the type of project.These are typically:60-70% Procurement20-25% Energy15-20% TravelGood building design, masterplanning and site selectioncan influence the operational carbon attributed to buildingenergy and transport.In this section we explore how the ‘Lean Clean Green’approach to design can have a significant impact on ahealthcare building’s operational carbon.6/24Unregulated carbon emissions within a healthcaresetting are a significant proportion of the NHS’semissions. Typically, the procurement and travelcomponents of carbon make up circa 75% to 85%of total operational carbon.BUILDINGENERGY20-25%
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMO P E R AT I O N A L C A R B O NThe ‘Lean Clean Green’ approach offers a practical designframework to navigate through a project’s development tooptimise the opportunity for a fully sustainable outcome.This approach is explored in more detail in this sectionof the guide.Achieving net zero carbon design will require a significantcarbon reduction below what is currently laid out forbuilding energy use in Building Regulations Part L.It’s therefore important to maximise the opportunities forlower energy solutions from the inception of a project.BENCHMARKINGThe Royal Institute of British Architect’s 2030 ClimateChallenge publication provides metrics for benchmarkingnon-domestic buildings as follows:B U I L D I N G R E G U L AT I O N SBe Lean:Use less energyENERGYEFFICIENCYTA R G E TBe Clean:Supply energy efficientlyBe Green:Use renewableenergy7/24The designapproachD E S I G N A P P R O A C H F O R R E D U C I N G O P E R AT I O N A L C A R B O NON SITECARBONREDUCTIONOffsetZEROCARBONTA R G E T2020 targets 170 kWh/m2/y2025 targets 110 kWh/m2/y2030 targets 0-55 kWh/m2/yThese targets may not apply to highly technical healthcarebuildings but provide a good starting point.CaseStudy:MANCHESTER PROTONBEAM THERAPY CENTREVIEWK I N G S H E A LT HPA R T N E R S H I P C A N C E RC E N T R E AT G U Y SVIEWGUYS TOWERRECLADDINGVIEWJERSEYH O S P I TA LVIEWUCLH PHASE 4 PROTONBEAM THERAPY CENTREVIEW
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMO P E R AT I O N A L C A R B O NReducing energy consumption is essentialto reduce the carbon emissions of healthcarebuildings. An important first step is to considerpassive design measures to prevent excessivesolar gains during the summer or heatescaping during the winter.O P T I M I S E S PA C EA L L O C AT I O N F O RV E N T I L AT I O N I FPOSSIBLEV E N T I L AT I O NThe building orientation and form can have a significantimpact on the ability to employ passive design measures.For example, buildings with deep plan forms can bedifficult when considering natural ventilation or a mixedmode approach.Healthcare buildings have several highly technical spacesthat demand high air-change rates to control infection.This can often lead to sealed facades with centralisedmechanical ventilation supplying and extracting air.Creating spaces with depth to height ratios of between2 and 2.5 will allow for single-sided ventilation. Thisworks well for wards, single bedrooms and consultantspaces. Similarly, locating buildings to allow naturalventilation, with minimum solar gain, can significantlyreduce the operational carbon.However, there are spaces within healthcare buildings thatcan be designed with either natural ventilation or a mixedmode approach. An early appraisal of the proposed spatialarrangement can help maximise the opportunities for suchan approach. For example, in many instances generalwards, circulation spaces, offices and open-plan waitingareas can be located to avoid fully mechanical solutionsreducing operational carbon emissions.CONSIDERO R I E N TAT I O NAND FORM WITHR E L AT I O N T OD AY L I G H T A N DSOLAR GAIN8/24LeanDesignO R I E N TAT I O N A N D F O R M
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMO P E R AT I O N A L C A R B O NU - VA L U E SAIR LEAKAGEA well-designed building envelope shouldrespond to external influencing factors suchas orientation, climate and occupancy. Ideallyit should use passive design measures toreduce the need for internal lighting, maximisenatural daylighting and provide good levelsof natural ventilation where appropriate.A U-value quantifies the amount of heat that can transferthrough a particular building fabric element. The lowerthe U-value the less heat is transferred. As an example,increasing the thickness of insulation in a wall build-upwill reduce the amount of heat that can pass through itand hence the wall will have a lower U-value.With any building typology, maintaining high levels ofinsulation and low levels of air-leakage can reduce the heatlost to the external environment. This approach can limitthe energy use, and hence carbon emissions associated withthe ventilation and heating or cooling of spaces.The balance between daylighting, solar gains and artificiallighting should be considered prior to developing thefaçade treatment.Solar shading can be a positive way of reducing the gainswithin spaces – helping to reduce operational carbon.A poorly orientated building with high glazing ratios(60-75%) may require excessive external shading tocontrol heat-gains. On the other hand, low glazingratios(less than 20%) may lead to an increased need forartificial lighting which can increase operational carbon.Another consideration is that good daylighting withinhealthcare spaces is recognised to improve patient recoveryand wellness, potentially speeding recovery and reducingthe length of stay.Achieving reduced air-leakage with a significantimprovement above the limiting legislative guidance(Part L) can reduce similarly reduce energy consumption.An optimum value of 20% improvement on Part L can bea good starting point; e.g. 2 m³/m²/hr @ 50Pa.9/24G L A Z I N G A N D D AY L I G H TA good façade performance will also reduce the energyusage of the building thereby reducing carbon emissionsand saving on energy bills. Optimised U-values should bechallenged to avoid insulating, which could lead to overheating or over- cooling. This can be a challenge wherehigh internal heat- gains from key equipment are expected.FA B R I C - F I R S TAPPROACHCONSIDERINGAIR-LEAKAGEA N D U V VA L U E SMAXIMISED AY L I G H T
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NO P E R AT I O N A L C A R B O NH E AT I N GCOOLINGWINDOWSIZEH VA CPLANT SIZESOLAR GAINV LIGHTD AY L I G H T10/24The baseline energy model is fundamental, and usingparametric modelling approaches during projectdevelopment ensures the initial design decisions areinformed and offer the best solution.CHALLENGING THE NORMENERGYO P T I M I S AT I O NMODELLING APPROACHBalancing all these considerations to identify themost sustainable, low operational carbon solution canbe challenging. At Arup, we advocate undertakinga parametric study. This study considers each of theparameters that impact on achieving a low operationalcarbon solution. Our ParameterSpace software can thenbe used to visualise the results and identify the optimalcombination of inputs (e.g. glazing area or façade thermaltransmittance) to achieve the required design outputs(e.g. carbon emissions and cost).EMBODIED CARBONThe image on this page shows this parametric modellingapproach when considering window size. Window size hasimplications on daylight, heating and cooling requirements,which in turn have knock-on impacts on the naturalventilation strategy, which is being explored in theblue section of the image.LOW ENERGYV E N T I L AT I O N S Y S T E MSOLAR ASSESSMENTUsing tools to optimise the designs solutions is a veryimportant part of the early stages of the building designprocess.Tools such as ArupSolar have been developed to look athow key aspects of the building design can be adjustedin real-time to assess the impacts. This can significantlyreduce the architectural/façade workflow process, allowingmultiple design options in real time.Our software assesses and develops efficient façades andglazing strategies, including solar gains, daylighting,external shading requirements and PV/solar thermalanalysis.ACOUSTICAIR QUALITYOPENINGWINDOWSSOLAR GAINV LIGHTGLAINGAREAD AY L I G H T
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMARUP SOLAR TOOL OUTPUTAs an example, utilising our parametric design softwareyou can see how varying the building form and facadecan optimise the operational carbon, before consideringthe engineering systems.0BASELINE1O R I E N TAT I O N2G L A Z I N G G - VA L U EO P T I M I S AT I O N3U - VA L U EO P T I M I S AT I O N4AIR PERMEABILITYO P T I M I S AT I O NStarting point – completed Stage 4 designAdjusted orientation by 10 – to optimise heating and cooling performanceCumulative Saving-0.5-1.5%Using parametric optimisation the g-value for the glass (the amount of solarenergy the building receives) can be tested and an optimal value calculated – inthis case the balance is delicate between heating and cooling loads, but a clearsaving is possible2.5-3%Similarly to the above the thermal performance of the façade can be optimisedfor further savings4.5-6%Air permeability optimisation – by targeting a lower air permeability a significantenergy saving can be made – however there is also a balance to be struck againsthearting and cooling performance11-13%11/24Description
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROO P E R AT I O N A L C A R B O NCleandesignOnce the building form, orientation and facade isoptimised, developing a strategy to reduce remainingenergy focuses on minimising energy and optimisingsystems. This clean design approach looks to reduceremaining energy.ARUP APPROACHO P E R AT I O N A L C A R B O NUnregulated energy includes small powerelectricity use such as:V E R T I C A L T R A N S P O R TAT I O NCOMPUTERS,PLUG IN DEVICESLAB AND MEDICAL EQUIPMENT(MRI, LINAC, ETC)C AT E R I N G E N E R G Y C O N S U M P T I O N .CHALLENGING THE NORMUnregulated energy not included within the Part Lassessments can form a significant part of overall energyconsumption and CO2 emissions from developments.Unregulated energy demands are included withinenvironmental assessment methods such as BREEAM,with an emphasis on reduction.The operational carbon needs to consider these elementsfrom the start of the project. Analysing the project briefcan identify where unregulated energy demands originate.After implementing passive measures, the remainingsystems that contribute to operational carbon emissionsshould be optimised. This process should consider theprimary energy use and how to reduce these demands.This can be challenging in a healthcare setting where thereare signifcant technical spaces.12/24As described earlier, operational energy within healthcaresetting is typically 20-25% of the operational energy.This energy use is divided into two groups: Regulatedand Unregulated.EMBODIED CARBONRegulated energy sources are those controlled by buildingregulations, as follows:S P A C E H E AT I N GH O T W AT E RS PA C E C O O L I N GLIGHTINGAUXILIARY LOADS( P U M P S , FA N S A N D C O N T R O L S )50%R E G U L AT E D50%U N R E G U L AT E D
CONTENTNET ZERO AND THE NHSDEFINING NET ZEROARUP APPROACHO P E R AT I O N A L C A R B O NEMBODIED CARBONCHALLENGING THE NORMO P E R AT I O N A L C A R B O NPLANT EFFICIENCYREDUCING LIGHTING DEMANDSTo impact operation carbon it's important to considerthese elements from the start of the project. Analysingthe project brief can identify where unregulated energydemands originate.Space planning is an important part of healthcare design,where clinical function requires detailed consideration ofthe adjacencies of spaces. This can lead to principal plantlocations being a secondary concern.After implementing passive measures, the remainingsystems that contribute to operational carbon emissionsshould be optimised.Decentralised plant is often adopted for key technicalspaces, such as theatres or critical care spaces, resulting inrisers and distribution losses having a negative effect on theembodied and operational carbon. For example, large riserson floor spaces increase the building area and create longdistribution runs, increasing distribution losses and energydemand. Adopting a localised plant strategy may improvethe operation carbon.Reducing lighting demands can be achieved using acontrol system. These systems not only reduce operationaldemands but can also vary the output and colour of lightingthroughout the day. Lighting levels and colour temperaturescan be varied to mimic natural daylight patterns andgive occupants the experience of a more dynamic,natural environment.This process should consider the primary energy use andhow to reduce these demands. This can be challengingin a healthcare setting where there are significanttechnical spaces.MINIMISING PRIMARY ENERGYOPTIMISE PLANTEFFICIENCY ANDC O N S I D E R L O C AT I O NOF PLANT13/24Minimising primary energy demand through improvedsystem efficiency needs to look beyond regulated energyloads of fixed building services, i.e. those that areconsidered in Building Regulations compliance modelling.It’s important to target unregulated loads such as medicalequipment, which can be significant contributors to energyconsumption and be direct sources of overheating.Adopting the Energy Use Intensity (EUI), kWhr/m2,metric as a critical parameter assessing the overallenergy consumption and efficiency of the buildingand benchmarking against similar buildings.REDUCELIGHTINGDEMANDSU N D E R S TA N D I N G M E D I C A L E Q U I P M E N TUnderstanding the size, capacity and re
Net Zero and the NHS THE EMISSIONS CHALLENGE Building design in the UK faces an unprecedented . Typically, the procurement and travel components of carbon make up circa 75% to 85% of total operational carbon. OPERATIONAL CARBON SPLIT The split of embodied carbon on a non-domestic project varies depending on the type of project.
a Net Zero Carbon Pathway, setting out how they plan to deliver “net zero carbon” real estate investments by 2050 at the latest, as well as publish progress towards this goal annually. There is currently much ambiguity surrounding the definition and scope of “net zero carbon” commitments. This is certainly true in the property
emissions ('net zero emissions') has grown, so has the need for a common understanding on what net zero emissions means and how to achieve net zero goals. Investors are also putting pressure on companies to lay out their plans for reaching net zero emissions and to demonstrate how net zero pathways are integrated into their long-term strategy.4
The Net-Zero riteria are part of the STi’s Net-Zero Standard. The Net-Zero Standard, which entails both the Criteria and forthcoming Net-Zero Guidance, will be finalized by November 2021 in advance of the 2021 United Nations Climate Change Conference (COP26). Public consultation of the Net-Zero Guidance is scheduled to begin in July 2021.
List of Figures, Tables and Boxes Figures 2 Figure S1 Overview of the key nuances of net-zero target implementation approaches 5 Figure S2 Ten basic criteria for net-zero target transparency 14 Figure 1 Internet searches for net-zero emissions 15 Figure 2 Map of cities and regions pursuing net-zero emissions 16 Figure 3 Population of cities and regions with net-zero targets, by geographic region
China net zero and job creation: Potential for the creation of c.40 mn jobs by 2060 33 Laying out the path to a net zero China: A sectoral deep dive 34 China net zero: The role of carbon sequestration 61 China net zero: The potential implications for natural resources demand 64
5 The Road to Net-Zero Finance The AGF's Recommendations for delivering net-zero finance in the UK A. Strategic 1. The UK should commit to be the world's first net-zero financial system 2. Make net-zero projects and plans investable, by increasing the predictability of cash flows and reducing risks through sector pathways, carbon pricing and de-risking
Achieving Net Zero Embodied Carbon in Structural Materials by 2050 SEI Sustainability Committee 1. May 2020 Executive Summary Structural materials (i.e., steel and concrete) are responsible for over 10% of global carbon dioxide emissions. This paper outlines five paths to achieve a net zero-carbon future within the built environment.
commitment to achieve net zero carbon emissions for the sector by 2030. The water industry is the first sector in the UK to commit to net zero carbon emissions by 2030. The 2030 target will not simply demonstrate that the water sector is taking its role seriously. It will also serve to provide leadership in the delivery of a net zero UK economy.
