Trends in Sustainable Solutions in the Built Environment 2023

This report summarises a range of solution trends that UKGBC has seen over the course of 2023, also providing context on their use and driving forces in the UK market.

The built environment spans diverse disciplines and connects many sectors, with innovations being developed and adopted across buildings and construction sites, but also within communities, think tanks, academia, acceleration programmes, and corporations. Much of this centres around addressing the climate and ecological crises and harnessing the potential of our built environment as a force for good.

It can be challenging to keep up with the latest developments in sustainable innovation, but UKGBC is continuously sourcing and profiling impactful solutions, talking to both innovators and the industry adopting them to understand their impacts. 2023 presented challenges for both VCs and start-ups, but we are still seeing much activity. Here we summarise a range of sustainable solution trends that UKGBC has seen over the course of 2023, also providing context on their use and driving forces in the UK market.

Innovative solutions are not always new technologies or products. In parallel to developing novel innovations, achieving UKGBC’s vision for a sustainable built environment requires our industry to more widely and rapidly implement the innovative, market-ready solutions that are already available to us. Further, while some solutions directly tackle specific challenges, others are more systemic, helping to create the conditions under which other solutions can be adopted at greater scale and pace.  We need a systems thinking approach when it comes to solution development and adoption. Implementing complementary innovations together can provide far more significant outcomes than implementing them in isolation, and the knock-on impacts or unintended consequences of any solution on the wider system should always be carefully considered. Especially in the complex built environment value chain. 

Themes of key trends in 2023:

UKGBC does not formally endorse any of the solutions presented in this report. It is intended as a signpost and to offer a source of inspiration for built environment stakeholders, who should always carry out their own due diligence before adoption. While this is a summary of some of the notable solutions UKGBC has seen, there are of course many other solutions available but not mentioned. 

Incentivising and Enabling ESG Outcomes

Organisations hold significant power to leverage change. Factors such as organisational purpose, governance, and financing structure shape how they act within and influence the wider system. With more organisations across our industry now transitioning towards net zero, this inherently alters the ways in which they also go about planning, constructing, maintaining, operating, occupying, and deconstructing buildings – with knock-on impacts for our wider economic and social systems. The social element of ESG also continues to gain traction, with organisations increasingly considering the impact they have on individuals, communities, and society.

The most progressive organisations are further seeking to go beyond traditional approaches to ESG and net zero by actively leaving a net positive impact on both human and natural systems. Achieving this requires innovation in business models. We are seeing the B-corp movement gain traction with built environment organisations, and other novel approaches evolving for replication like Riversimple pioneering a Future Guardian Governance structure, and Faith in Nature putting nature on its board. 

However, the landscape around organisational ESG monitoring and reporting remains complex, not least due to the huge range of compliance standards available and required in different locations, and the resource and expertise required to align with these. There are various solutions emerging to help simplify these processes, including Company Tracker Pro, OnePlanet Digital, Deepki, Measurabl, EcoVadis, and World Wide Generation. Some platforms also integrate novel approaches towards change management, for example Giki supports and empowers employees to build individual and collective sustainable behaviours in support of their organisation’s climate goals.

When it comes to ESG outcomes on projects, organisations cannot operate in isolation and complex value chains within the built environment can be a hinderance. Solutions that enable effective and efficient collaboration and alignment of incentives are key. Integrated Project Insurance, for example, is a new delivery model that replaces professional indemnity insurance with a collective insurance product for all project partners and supports a “blame-free” culture. Progressive organisations are also investing in their supply chains to support the scaling-up of the sustainable materials and technologies needed to deliver on their commitments, with knock-on benefits for the whole sector.

Innovation in sustainable finance is also beginning to make waves. The Atelier Carbonlite Challenge, for example, links the interest rate of financing to actual building performance around operational energy, embodied carbon, and water consumption. Sustainable finance issuance has also seen growth in the past few years, further incentivising sustainable outcomes on projects.

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Climate Risk, Resilience, and Adaptation

Physical risks associated with climate change, and our ability to adapt and build resilience, is a growing area of concern and focus that presents many challenges. UKGBC is beginning work on a Climate Resilience Roadmap for the built environment to set measurable indicators, metrics, and evidence-based targets for climate resilience and to identify a pathway for key actions and policies across the industry.  

Risk assessment and insurance

A key challenge in this area is the lack of data available to accurately measure and anticipate our level of risk to climate exposures. Interdependencies between risks and hazards add to this challenge. For example, the impact of flooding after a drought is often exacerbated as the ground is less permeable to stormwater. Climate hazards also don’t apply neatly to individual assets or developments, but instead often impact streets or communities as a whole. So, we can’t think at an individual project scale. For example, measures to protect one property may have negative knock-on effects on others, requiring holistic and systems-thinking approaches towards their implementation. Solutions do exist to try and help planners and developers understand their options for climate resilient urban design, such as Greenpass. 

Due to the uncertainty in the timing and extent of future physical hazards, stakeholders often remain unclear on which adaptation measures to prioritise. There are also differences in risk appetite, incentives, and capacity to adapt between organisations. It tends to be the larger and more financially robust organisations undertaking – with many now required to undertake – detailed climate risk assessments. Various digital platforms are emerging to support organisations in understanding and evaluating climate risks associated with their portfolios. These include Climate X, Intensel, EarthScan, Waterplan, Raincoat and Climanomics. However, different tools can produce different hazard risk profiles for the same or similar properties, meaning that transparency in data, granularity, assumptions, and climate scenarios used is vital to enable users to understand results. However, it isn’t just existing portfolios at risk from climate hazards, construction sites are also vulnerable to the increasing frequency of extreme weather events either directly onsite or via supply chain disruptions. Solutions to manage and mitigate this risk are emerging, like EHAB, which provides granular analysis of weather risk on a construction project.

With a growing need to understand and mitigate climate risk, novel approaches towards insurance can also offer both challenges and opportunities. Under continuing climate change scenarios it is likely that buildings will become increasingly uninsurable, but there are some innovative insurance products emerging. One example is parametric insurance, which automatically pays out a pre-agreed amount when certain climate parameters are met. FloodFlash is a commercial insurance product that follows this model, automatically paying out once a certain depth of water is reached during a flood event. This automation lowers premiums as it reduces uncertainty and costs, and can be further improved by investing in flood defence measures. However, there remains a concern that due to climate risks and uncertainty, insurance is becoming increasingly expensive to purchase. As noted by the EIOPA, insurers have the opportunity to help address this and incentivise positive action by developing more innovative products that provide cheaper premiums to policy holders implementing climate adaptation measures.  

Adaptation approaches and action  

The adaptation pathways approach is a decision-making solution with great potential, used for the Thames Estuary Adaptive Plan and by many others. It includes exploring multiple adaptation pathways so as not to lock decision-makers into a single route forwards that may prove inappropriate for the emerging climate. The approach acknowledges future unknowns and the fact that we need a range of viable options to address risk effectively. The Adaptation Catalyst E-Tool is another tool that can help users identify the best adaptation measures through incremental, integrated actions under uncertainty. 

Flooding

A major hazard in the UK is flooding. Solutions to combat this can be implemented both outside and inside a project boundary, for example through creating permeable ‘sponge cities’, implementing nature-based solutions (with their many co-benefits), and building city flood management infrastructure. More direct solutions include smart air bricks, raised services, closed cell insulation and flood doors, for example.   

To give homebuyers and tenants an indication of their flood risk before they buy or sign a lease agreement, industry is considering the use of Flood Performance Certificates, inspired by Energy Performance Certificates. This type of scheme could motivate further solution development and deployment to improve flood resilience, with potential for the concept to be scaled up to other sustainability indicators.  

Overheating

Overheating is another hazard that is growing quickly in severity in the UK. Various solutions exist that seek to address this. First, there are low-e window films that can be applied to glazing to reduce overheating.  Examples include MicroShade which uses micro-louvres to prevent excessive summer solar gains, Albotherm which reversibly transitions from transparent to white at certain temperature points, and Filia which has solar integrated shutters that reduce overheating whilst also increasing surface area available for renewable energy generation. There are also traditional, passive external shading solutions like louvres, brise soleil, and shutters. These are simple yet effective and, unlike many tech solutions, don’t require rare earth materials to make or necessarily result in hard-to-recycle composites. 

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Nature and Biodiversity

Climate Tech has been gaining traction for a while, but another area seeing increasing innovation is Nature Tech. There are a number of factors driving this, stemming from increasing awareness of nature-related risks. The Taskforce on Nature-related Financial Disclosures (TNFD) assesses organisations’ impact and dependencies on nature, and it’s likely (although not confirmed) that mandatory reporting will be incorporated into regulation within the next 5 years. The UK’s National Planning Policy Framework is also likely to cover nature and adaptation, favouring small-scale nature-based solutions. Further, legislation around Biodiversity Net Gain (BNG) as part of the 2021 Environment Act is also impacting innovation. For large sites this comes into effect from January 2024 and small sites April 2024, mandating at least a 10% BNG on most new developments requiring planning permission. More broadly, defining consistent and comparable monitoring metrics and indicators around nature and biodiversity is a major challenge, although Science-Based Targets for Nature is seeking to address this. There are many interrelated factors to consider, like air and water pollution, habitat impact, knock-on ecosystem effects and so on, and difficulties expressing this complexity in metrics.

Biodiversity Net Gain

BNG can be achieved on-site, off-site, or compensated for through statutory credits as a last resort. In response, many new tools are emerging to help developers baseline, test, and monitor the impact of their schemes on biodiversity. These include Joe’s Blooms, AiDash, Gentian, Biodiversify and Map Impact. However, challenges remain around upskilling and training around BNG, particularly for local planning authorities. Verna supports local authorities and developers through end-to-end support, from assessment of planning applications to the subsequent 30 years of monitoring and reporting.

Embodied ecological impacts

There are growing calls for Life Cycle Assessments to look at more than just climate impacts and to consider wider sustainability metrics such as embodied ecological impacts. However, we need greater transparency in supply chains around this topic and it is particularly challenging to assess and locate impacts when they are not directly linked to an organisation. One emergent solution provider is Firstplanit, which presents sustainability metrics of materials beyond embodied carbon. The platform also recognises the importance of context, suggesting sustainable products or materials by evaluating a variety of factors such as use-case and location.  

Value of nature

There are also challenges when it comes to quantifying the value of nature. UKGBC has undertaken work on valuing urban nature-based solutions, and many other organisations are also seeking to explore the potential to create a financial business case for implementing them. Hoare Lea’s tool – Biome – for example, looks at both the monetary and non-monetary value nature creates. Allocating financial value to nature may unlock new solutions, such as payback schemes for those benefitting from nature-based interventions, but this also brings complexities due to the variety of co-benefits and stakeholders involved.

There is increasing demand for accessible nature spaces in urban areas, also recognising the value of human connection to the natural world in maximising positive actions and outcomes. We must recognise the importance of building local understanding and knowledge around nature, which cannot always be quantified. Engaging local communities in initiatives that enhance nature is likely to create longer-term value and promote maintenance of solutions once implemented. Tiny Forest, for example, engages local communities, schools and businesses in planting, maintaining, and monitoring forests to foster a sense of co-ownership.  

Physical interventions and monitoring and design tools

There are a host of individual solutions available to enhance nature and biodiversity, such as bee and bat bricks, living street lights, multifunctional planters, and innovative tree planting initiatives. However, to avoid tokenistic deployment, a localised and contextual approach towards finding the most appropriate interventions is required. Various solutions exist to support this, including the innovative use of sound technologies (see AgriSound) and eDNA (see NatureMetrics) to analyse sites. There are also platforms that help with decision-making. These include a design tool to assess the natural capital and biodiversity impacts of street trees, NATURE Tool for assessing land use change impacts on natural capital, and Nature4Cities, a “one-stop-shop” for nature-based solutions. 

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Embodied Carbon

There are still no formal plans for the UK to follow the European Union in introducing national embodied carbon limits for construction. That said, the National Planning Policy Framework consultation (December 2022 – March 2023) did consider mandating Whole Life Carbon Assessments (WLCA) for planning purposes, and some Local Planning Authorities are already striving for this. The London Plan, for example, requires development proposals to calculate and reduce WLC emissions. This is already resulting in some being challenged and ultimately rejected on whole life carbon grounds. Further, following the Levelling Up and Regeneration Act 2023, local authorities will be required to create local design codes that – if following the template set by the national model design code – would include embodied carbon information. Against this backdrop, and in anticipation that more rigorous embodied carbon regulation may follow, various innovations are gaining traction.  

In order to reduce embodied carbon, we need to accurately and comparably measure it. Many calculation tools are now being widely used by practitioners, including Cercula, EC3, eTool, One Click LCA, and Preoptima. However, as highlighted in UKGBC’s Embodied Carbon Modelling and Reporting Guidance, improving alignment and exchange of methodologies and datasets used by these tools is critical. Modeler capability also has a significant impact on the quality of WLCA results, but there is currently no formal verification process for ensuring levels of competency among practitioners. Construction Carbon are seeking to address this by providing a training and verification route for practitioners.

To produce accurate WLCAs we also need reliable input data, ideally product-specific Environmental Product Declarations (EPDs), but also generic sector-level data (which can be sourced from ICE, IMPACT, and BECD databases, or sector-level EPDs). The EPD process is not well digitised, with outputs often in PDF format, many manual workflows, and frequent recalculations being required to reflect evolving manufacturing processes. 2050 Materials has suggested that automation through artificial intelligence (AI) could help streamline some of these processes; reducing costs, improving reliability and increasing efficiency. The OpenEPD framework, ECO Platform, and US-based Smart EPD are also seeking to help address some of these challenges. 

Another area where innovation is taking place is early-stage design optioneering around embodied carbon. Solutions like Preoptima use generative design to analyse thousands of design options and return the most optimised choice for reduced whole life carbon, and One Click LCA’s Carbon Designer 3D can be used to compare and visualise carbon performance of design alternatives. 2050 Materials and Tangible Materials can also help with early-stage building material comparison and selection to minimise and report on embodied carbon.

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Circularity and Waste

The built environment currently accounts for around 60% of the UK’s material consumption and nearly half of all waste. Transitioning to a circular economy is therefore an increasingly important topic, with novel means to promote circular economy principles flooding into our industry. The UK’s Circular Economy Package sets out our broader legislative framework around circularity and waste, but for the UK built environment local government also remains a key driving force of progress and innovation. Particularly notable, Circular Economy Statements have been mandatory for large-scale developments in London since 2021 under the London Plan.

Circularity metrics

There is growing frustration at the lack of consensus on circularity metrics for materials and buildings, something UKGBC’s Circular Economy Forum has explored in recent work. However, in response, there are an increasing number of solution providers looking to support this, such as Upcyclea, with a Circular Signature to measure the circularity of a given building, or One Click LCA’s Circular Economy Tool. Improved consensus on these metrics would help inform material and design choices and enable positive recognition of good practice across the industry.  

Material reuse

Material reuse particularly continues to gather interest as a means to reduce waste, virgin material extraction, and embodied carbon in promotion of  a more circular economy. One focal point of this discussion is steel, as companies like Cleveland Steel and Tubes recover material from steel mills and the oil and gas industry for use in the construction sector. Various digital tools are also emerging to match reused steel stocks with building designs, like the HTS Stockmatcher and FerrousWheel. To help accelerate the reuse of materials more widely, exchange platforms have also been scaling at speed, for example the Material Reuse Portal, Enviromate, Sustainability Yard, Globechain and Loopfront. Reusefully is even using AI to automate the material recognition and upload process to its platform. As identified by UKGBC’s recent report on System Enablers for a Circular Economy, this shift towards a more circular economy has a variety of different enablers, including a strong social and community focus. Innovators are responding to this, with maker and repair communities (see Pop-Machina), libraries of things (see Tulu), and reuse shops and services (see Mökki) emerging.

Material passports

In recent years, material passports that enable materials to be more easily reused or recovered at end of life have emerged as a key solution for driving circularity. Various digital platforms are being created to support their roll-out including Madaster, Circuland and Upcyclea. Data from these platforms can be aggregated to building, or even city, level to give decision-makers insight into the materials in use across the built environment, enabling better planning for future material recovery and reuse, and to understand long-term economic value. Data for material passports can come from a variety of sources, like BIM models, EPDs, bill of quantity, Circular Economy Statements and pre-deconstruction audits. The latter is particularly important for the UK as we commonly lack information on material make-up for existing buildings. Material Index and Reusefully’s PreaDeM both seek to digitise the material pre-deconstruction auditing process and make it more efficient.

Recycling and tracking materials

Moving down the waste hierarchy, recycling rates of construction and demolition waste in the UK are generally high, but this is mostly achieved through downcycling that results in a loss of quality. Across the industry there is therefore growing interest in tackling materials that are hard to recycle or recover such as flat glass, plasterboard, concrete, and even construction PPE and workwear, with innovators like Xeroc and Stuff4Life seeking to support. 

When you scale all this up, the wealth of information that project teams need to accurately track and assess the impact of their material choices is extensive, especially when you factor in regulatory, certification, and language variation across geographical locations. Various digital tools are available to consolidate this information, like Qualis Flow who can help with the tracking of materials on site to alleviate administration and reporting pressures.

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Innovative Building Materials

More sustainable building materials are being developed and incrementally improved all the time. Although a recent A/O PropTech report found the use of “green” materials still typically entails a 10% cost premium, the Government is considering policies to incentivise their use. Primarily, the UK Carbon Border Adjustment Mechanism (out for consultation in 2024) would apply a carbon price on some of the most emissions-intensive industrial goods like cement, aluminium and glass that might level out the playing field.   

Concrete

One of the biggest carbon hitters in construction is concrete, responsible for around 8% of emissions globally. Whilst minimising its use should be the priority, there are cases where concrete currently remains the most appropriate material choice, meaning that its decarbonisation is a focus for many innovators. Some are using alternative aggregates, like mixed construction and demolition waste (currently being explored by Salford University), while others are using unrecyclable plastic waste (see Low Carbon Materials) or manufactured limestone that utilises carbon dioxide to treat and valorise a range of wastes (see O.C.O Technology). With cement being the most carbon-intensive ingredient of concrete, some innovators are also developing novel solutions to reduce this, including Sublime Systems and Geoprime. While others seek to eliminate the need for cement altogether, for example Earth Friendly Concrete, who use a unique binder system that can result in up to 87% embodied carbons savings, Mevocrete which eliminates the need for OPC and heat, and BioZeroc’s cement-free BioConcrete. Others focus on drawing down carbon dioxide, using concrete blocks as a vessel for its long term storage, like CQuestr8. 

Returning to the need to reduce the amount of concrete required in the first place, solutions that optimise design are key. Hyperion Robotics has developed software to optimise structural designs for 3D printing of low carbon concrete, and minimass create 3D printed concrete beams – both resulting in minimal material usage – while Structure Pal uses AI to eliminate concrete over-design. 

Bricks

Various innovative bricks are also emerging. Kenoteq’s K-Briq is currently making waves across the industry, made from over 90% recycled construction and demolition waste with a production process that doesn’t require high temperature firing, virgin cement, or high volumes of clay. There are also project-tailored brick solutions that make the most out of local waste, like the Gent Waste Brick, or those that use recycled plastic like this brick made from plastic waste.  

Bio-based materials

Bio-based materials continue to gain traction, with national interest (particularly from the Scottish government) in scaling-up domestic production of materials like hemp. Innovators such as IndiNature and Unyte Hemp are responding to this, IndiNature having signed the largest industrial hemp supply agreement in the UK. Beyond insulation, other innovative uses for hemp include BioTwin’s low carbon hemp wall stud, and Adaptavate’s hemp-based ‘breathaboard’, a plasterboard substitute. Other bio-based insulation materials seeking to scale include mycelium (see Biohm and Mykor), meadow grass (see Gramitherm), and straw. Algae is even being used in paint to support carbon absorption (see Cyanoskin). Other applications of bio-based materials include high performing construction systems like EcoCocon and Natural Building Systems.  

Timber is another bio-based material increasingly used in construction, especially for structural purposes (but even for sanitary ware – see Woodio). However, insurance challenges are presenting a notable restriction. Seeking to address this, Built by Nature recently launched their New Model Building, a set of details for multi-storey mass timber housing pre-assessed by a UK warranty provider. Rosetta Risk Management also attempts to tackle these challenges by providing near real-time risk performance data to insurance providers, enabling more accurate risk measurement to decrease premiums and increase insurability of timber construction. While celebrating this progress, we must always also remain mindful of the embodied ecological impacts of using any bio-based like timber. 

Construction systems

There are also a number of innovators working on construction systems, ranging from high performing external walls (see Project Etopia) to reusable internal wall partitions (see Akustak and Juunoo), as well as whole house, zero carbon, and offsite solutions like ZED PODS, TopHat and Natural Building Systems. And there are digital platforms emerging to help facilitate the uptake of these, like hesti. Scaling solutions focussed on Modern Methods of Construction (MMC), however, has been an unusually significant challenge that has even lead to a UK Government inquiry. Despite this, the potential benefits of MMC do remain clear and there are examples of modular housing seen both overseas and in the UK, for example Crofts Street in Cardiff. 

Scaling-up innovative materials

With all innovative materials, a major challenge is scaling-up their production at the pace required, often due to high upfront costs and the large quantities of materials required. For materials that are more easily embedded into existing supply chains and manufacturing processes, licensing can be a viable option by allowing a solution-provider to grant another manufacturer rights to production, speeding processes up. However, other materials require more drastic changes to existing supply chains – in some cases the creation of new ones – to scale. US-based Carbon Title is investigating methods of bringing together multiple organisations to co-invest in their supply chain, unlocking future sustainable material use at scale. Collaborative approaches also have the potential to de-risk the implementation of solutions, for example when larger developers invest in testing and piloting on lower risk projects, they can help make solutions cheaper for initial implementation before economies of scale are reached and provide case studies with an evidence base for wider adoption. Increasing industry awareness of innovative materials and providing greater transparency around their sustainability credentials can also improve confidence in their use. NBS Source offers one such resource – having added a ‘sustainability data’ filter to their database – and previously-mentioned platforms like Firstplanit, 2050 Materials, and One Click LCA are also available to inform material selection. UKGBC’s own Solutions Library also showcases a range of impactful and innovative sustainable building materials. 

Another challenge faced by material innovators looking to scale is risk aversion across the construction industry. Demands for expensive testing and certification, including EPDs to prove environmental credentials, often stymy uptake. Funding incentives or rebates for undertaking these processes on lower impact construction materials could support their adoption, similar to the scheme announced by the Environmental Protection Agency in the US. 

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Carbon Offsetting

To reach net zero, it is essential that we follow a science-based decarbonisation pathway that prioritises reducing emissions in line with 1.5oC, before evaluating options (including offsetting) for any residual emissions. The buildings industry has seen a sharp and considerable uptake of net zero targets and the voluntary carbon market – where offsets are purchased – continues to be unregulated, which can make purchasing offsets challenging. In 2023 carbon offsetting also received criticism, with claims around the worth and impact of projects being scrutinised. With the spotlight firmly on, offsetting has become an increasingly interesting area for innovation. 

UKGBC recently published updated Carbon Offsetting and Pricing  Guidance to enable better decision-making and responsible offsetting. It provides a step-by-step process to enable a holistic approach to ambitious carbon offsetting and encourage the wider adoption of internal carbon pricing as an additional and complimentary mechanism to accelerate the decarbonisation of the built environment.  A related area of innovative thinking that continues to gain momentum is the transition fund approach. This involves an organisation setting an internal carbon price for which the proceeds are placed into a fund and used in part to purchase offsets, with the remainder allocated towards broader climate action. Transition funds can also be invested in carbon insetting, which involves the scaling of sustainable technologies and decarbonising of organisational supply chains – a spur for innovation and solution deployment. A leading approach, as identified in UKGBC’s guidance, is to pool transition funds between projects or organisations, to provide larger and more impactful investment opportunities and minimise management fees. Arup and BusinessLDN have partnered to explore the creation of a collective, business-led carbon offset fund in such a way.

When it comes to offsetting, there is also growing consideration for the differences between global and local projects. Organisations are increasingly seeking UK-based projects to reinvest in the local economy, ensure co-benefits are felt locally, and improve the ability to visit and verify activities. Offsetting projects with co-benefits are themselves also a growing trend. Some options being explored in this space include offsets that help farmers transition to regenerative agriculture (see Agreena) and using offsetting to fund retrofit projects (see HACT, PNZ Carbon, and Snugg). Although these examples are both reduction rather than a removal offsets, they could form part of a broader offsetting strategy and be used as part of a transition fund approach.   

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Renewable Energy

Whilst celebrating the promise of solutions that facilitate our use of renewable energy explored in this section, it is also critical that we remain mindful of the need to bring down energy demand as far as possible to maximise their positive impacts. It is clear that we need renewable energy, energy storage, and electrification to achieve net zero, but many of the solutions available to facilitate this can bring negative sustainability implications of their own. For example, many technologies require the use of rare earth materials and can be high in embodied carbon, as well as there being broader social and ethical factors to consider in their supply chains. Solutions that transition us towards renewable energy should not be seen as a silver bullet – we still need extensive systemic transformation to ensure demand on the grid remains manageable and negative externalities are mitigated.   

Electricity

Decarbonising the UK grid by 2030 is critical to achieving our national Net Zero target. However, the closer we get to fully decarbonising the electricity system, the more challenging further decarbonisation becomes. A higher proportion of intermittent renewables – such as wind and solar – in the grid inevitably results in less predictable output, with increasing demand compounding these challenges as we seek to electrify our buildings and vehicles. More broadly, the grid is also transitioning from a system with centralised to distributed generators. This adds complexity by straining the physical limits of incumbent electrical infrastructure, which can both curtail the output from existing renewable generators and constrain or prevent the introduction of new renewables onto the system. As a result, we have seen wait times of up to 15 years for some renewable energy projects to receive permission to connect to the grid. This is exacerbated by the plethora of so-called speculative “zombie projects”, clogging up the connection pipeline ahead of projects that are ready and waiting to deliver power to the grid. Ofgem is seeking to help address this by removing any “first come first serve” basis for grid connection, and instead basing this on project readiness to connect.

Decarbonising the UK grid by 2030 is critical to achieving our national Net Zero target. However, the closer we get to fully decarbonising the electricity system, the more challenging further decarbonisation becomes. A higher proportion of intermittent renewables – such as wind and solar – in the grid inevitably results in less predictable output, with increasing demand compounding these challenges as we seek to electrify our buildings and vehicles. More broadly, the grid is also transitioning from a system with centralised to distributed generators. This adds complexity by straining the physical limits of incumbent electrical infrastructure, which can both curtail the output from existing renewable generators and constrain or prevent the introduction of new renewables onto the system. As a result, we have seen wait times of up to 15 years for some renewable energy projects to receive permission to connect to the grid. This is exacerbated by the plethora of so-called speculative “zombie projects”, clogging up the connection pipeline ahead of projects that are ready and waiting to deliver power to the grid. Ofgem is seeking to help address this by removing any “first come first serve” basis for grid connection, and instead basing this on project readiness to connect.

Innovation across the industry can support grid decarbonisation by breaking down existing silos between the energy system, transport sector, and built environment. Every building has the potential to act as a thermal battery, be smart and flexible, and to generate renewable energy to support a resilient, zero carbon electricity system. Similarly, every electric vehicle can contribute to the grid’s decarbonisation as distributed storage when plugged in. In this way, buildings and vehicles become part of the solution.  

Flexible buildings are able to respond to the availability of renewable electricity in the grid by timing consumption for when the grid is cleanest. This can be achieved through active demand management, including smart systems and appliances that prioritise the use of onsite renewables as far as possible and then respond to the carbon intensity of the grid. Technologies exist to help with this, including autonomous control and demand response solutions like Kapacity.io and OakTree Power. 

In many cases it won’t be possible to generate 100% of a building’s electricity on site. Renewable energy procurement is therefore a fast-growing area, with supporting platforms gaining commercial traction at a rapid pace. According to UKGBC’s guidance on Renewable Energy Procurement, electricity should be sourced from renewable sources and with an associated energy attribute (e.g. REGO), demonstrate additionality by driving the creation of more renewable capacity and supporting infrastructure (e.g. energy storage), and be time-matched as far as possible at an hourly resolution or better. These recommendations open up new areas for innovation, including time-based energy attribute certificates (T-EACs), further demand management and storage solutions, and platforms to manage and enable the use of Power Purchase Agreements (PPAs). Platforms that help with onsite generation and resale of renewable energy are also likely to increase in use. Good Energy, for example, has been informed by UKGBC’s guidance. It has 100% PPA-backed power and is also moving all half hourly metered business customers to an hourly matching product, providing transparency about what technology has produced their power and how much has been produced on an hourly basis. Digital platforms to help with renewable energy procurement also exist, including Lumen Energy, Verse and UrbanChain. 

When it comes to generating renewable energy onsite, there are many other areas of innovation. There is a diverse range of solutions on the market, including solar roofs (see Roofit.Solar), facade integrated photovoltaics (see SolarLab), solar shutters (see Filia) and balconies (see WeDoSolar), and mechanical facades (see Solskin) that track the sun and can adapt to provide different levels of shading. There are also solutions specifically designed to improve the performance of existing PVs – such as Window Insulation’s Solar Enhancer – and others that focus on improving the available options for solar power allocation, like SolShare which connects multiple apartments to a single rooftop system. Solutions are also emerging to address known challenges around recycling solar panels at end of life, including Solarcycle and Solar Materials.  

Energy storage

Energy storage is also a trending area of innovation, helping address challenges posed by the increased proportion of intermittent renewables in the grid and to maximise the benefits of onsite generation. This includes large-scale storage with technological solutions like Energy Dome and Our Next Energy, integrated business model solutions like Field, and Hybrid Greentech and thermal batteries like sand batteries or phase change material thermal storage. There are also smaller-scale storage solutions more suitable at the asset level, like Powerwall, or the option to reuse electric vehicle batteries in homes. Ampd Energy has further developed an energy storage system that provides diesel-free power for construction sites and can trickle-charge from the grid or onsite renewables to reduce peak loads. And then there are “virtual power plants”- networks of distributed energy production and storage devices that can be optimised virtually to stablise the network. Solutions in this area include Piclo, Peak Power and Axle Energy, helping buildings owners become “prosumers” of energy.  

Heat

Currently a large portion of the UK’s heating comes from gas, but we need to transition away from this to meet our net zero goals. Electricity can be used for heating most efficiently through heat pumps, which can demonstrate efficiencies of 250% or more. In addition, when combined with solar power, heat pumps can be optimised to maximise the proportion of any renewable power generated onsite that they consume. This has the added benefit that the maximum output from PVs often coincides with the warmest time of day, helping to improve overall efficiency and minimise the operating cost of an air-source system. In anticipation of rising consumer demand, heat pump technologies are experiencing significant development and innovation. Incrementally more efficient heat pumps are emerging onto the market, with other examples of innovation including Quilt’s ductless heat pump system and Kensa’s “Heat the Streets” project, which installed a communal network of ground source heat pumps to create a model for street-by-street heat decarbonisation.  

There are various models to enable and incentivise lower carbon heating. Octopus Energy’s Cosy Tariff for heat pump owners is one example, designed to encourage energy consumption during periods when energy in the grid is cleanest and cheapest. Heat as a Service is another novel business model seeing greater innovation and uptake, whereby consumers choose how much to spend on feeling warm in their home instead of paying for energy directly. Then there’s also Zero Bills, who fit homes with solar, storage, and a heat pump, then optimise consumption to result in a zero bills guarantee for five years. For properties with a large roof area and lots of sunlight, solar thermal can also be a good heating option. Although, worth considering the trade-off of reduced roof area for photovoltaics. To address this, there are innovations like Naked Energy’s Virtu PVT, which can generate both electricity and heat from a single solar collector.   

Challenges do remain, particularly around heat pump installation costs, despite the Government bringing in grants via their Boiler Upgrade Scheme and changing regulations to enable heat pump installation within 2m of site boundaries to improve viability in dense urban areas. We also need to ensure homes are ‘heat pump ready’, which can require significant fabric upgrades and radiator replacements to account for lower water temperatures and peak power outputs compared to gas boilers. Heat pumps and their associated system also need to be sized based on meeting the demand of the coldest day, which often results in oversizing for the majority of the year. Hybrid space heating systems can help address this, where a heat pump is supplemented by other electric heating solutions during peak demand periods. Therefore, some alternative space heating options include iHelios Living Reinvented’s invisible multi-zone smart heating system, which is controlled by app and occupancy, and Anzen’s wall-integrated heating and ventilation system.  

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Retrofit

Reducing the energy consumption of our existing building stock is critical to meet UK net zero targets, with a large portion of our housing in particular need. Venture capital money is recognising this, with retrofit companies attracting significant investment and recently seeing the fastest early-stage deal growth. Retrofit requires both top-down and bottom-up interventions, and although there have been various government schemes attempting to promote and incentivise retrofit, stop-start policies have meant patchy and insufficient progress. 

Many solutions to enable retrofit are mentioned in previous sections, including heat pumps, energy storage and PVs. However, truly scaling up retrofit in the UK requires coordinated progress in many different areas, from developing supply chains through to training new and existing installers, as well as raising understanding and awareness among building owners.

Digital solutions

There are nuances and conflicting motivations when considering the most appropriate combination of retrofit measures for any specific context. We have been seeing a significant increase in the number of companies offering “one-stop-shop” models for retrofit, which enable building owners to set priorities, understand their options, and sometimes even connect with installers. For home retrofit, notable examples include Furbnow, Propflo, Snugg, Hestia, Sero, Tallarna, PropEco, Ecofurb, People Powered Retrofit and Retrofitworks. For commercial buildings, CarbonShift, Mortar IO, Building Atlas, Perse and Skenario Labs. Other solutions focus on identifying priorities for home retrofit through heat mapping and analysis, like Kestrix for home retrofit and QEA Tech for commercial. Satellite Vu even takes thermal images from space to identify the most leaky buildings and cities, among other use cases.  

Physical solutions

As well as digital solutions, there are many physical innovations for retrofit. Insulation innovation is particularly prevalent, with several solutions already cited in the ‘Innovative Building Materials’ section. But new manufacturing and installation processes have also emerged, like Comfort Frame’s innovative Internal Wall Insulation, VundaHaus‘ prefabricated insulation kits, Q-Bot to robotically install underfloor insulation, Window Insulation‘s window coating, and Energy Saver’s sealing solution to increase airtightness. Continuing with the ventilation theme, Airex have also developed smart airbricks to reduce heat loss through intelligent airflow control. With other trending “smart” retrofit solutions including measurable.energy whose smart socket aims to eliminate small power wastage, and various intelligent radiator controls like EcoSync battery-free thermostatic radiator controls that heat rooms based on occupancy and need. 

When it comes to regulation, the Scottish Government is currently consulting on a proposed minimum energy efficiency standard for homes, as part of the upcoming Heat in Buildings Bill. Rather than require a specified energy performance, the standard proposes a list of measures that, if installed, mean building owners will automatically meet the standard regardless of the actual energy performance post-retrofit. This may present opportunities for innovators who are able to quality check retrofit solutions in retrospect, holding installers accountable and increasing confidence in retrofit measures. Such solutions could also support the creation of much-needed datasets and case studies in this space.  

It is important that any physical retrofit solution is carefully evaluated to ensure appropriateness and installed as part of a holistic strategy that considers any knock-on impacts, as well as wider impacts like climate resilience or human and nature health and wellbeing. PropEco exemplifies this approach, evaluating wider data beyond just energy performance for properties including information on current and future climate risk exposure and human wellbeing. Propflo, mentioned already above, also rates properties for wider metrics including their thermal comfort, indoor air quality and financial stability.  

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Smart Buildings, Optimisation, and Operational Efficiency

In addition to reducing the upfront resource consumption and embodied carbon of buildings, we need to minimise their operational energy use and energy use intensity. Many methods to do this are now well-understood and practiced by industry, including ensuring building fabric has a low u-value and high airtightness, but this still remains an area for further innovation This is supported by rising demand for meeting progressive standards such as the Passivhaus Standard, which denotes buildings that are high performing and require very little energy for heating and cooling, and the anticipated UK Net Zero Carbon Building Standard that will soon set energy use intensity targets for buildings claiming to be net zero.  

Collecting and analysing data

Complementary to “fabric first” approaches are methods to digitally optimise buildings for substantial energy consumption reductions. This can be achieved through making buildings themselves “smarter”, an area that has been rife for innovation for a while. This begins with collecting and analysing data, often through physical sensors and Internet of Things devices that continuously interact with the built environment to gather data. This can result in a variety of information from different sources providing insight into a building (including sensors, smart devices, meters and sub-meters, utility bills etc). Companies like MeterZ and Rhino Energy are amongst those looking to address challenges in gathering and interpreting this data. Building Operating Systems also offer a developing evolution of the Building Management System (BMS), which acts as a middleware between data and applications within the building. A holistic approach to smart device installation does still need to be taken, fully weighing up the potential sustainability benefits against any negative consequences such as the consumption of rare earth materials for hardware production.

Once data is collated, a growing number of solutions exist to analyse and present it on interactive and user-friendly dashboards that offer insight into opportunities for efficiency improvements, also helping with predictive maintenance and pre-emptive identification of faults. Notable examples include Demand Logic, Infogrid, Varig Technologies, BlockDox, Metrikus, Grid Edge, arbnco and CIM.   

Autonomous optimisation and air quality

Another layer of innovation is the autonomous optimisation of buildings, either through adaptation of an existing BMS or by installing new hardware. Autonomous control allows the reduction of energy and carbon associated with a building in operation, with notable companies working in this space including BrainBox AI, R8 Technologies, Elyos Energy, Arloid, Ecopilot, REsustain and Optimise AI. Even for buildings without a BMS, some of these solutions offer opportunities for optimisation.

Many of the solutions noted above specifically focus on automating the control of HVAC systems, an area that has seen notable activity and interest in the wake of the COVID-19 pandemic, helping to improve air quality in buildings alongside energy-savings. Urecsys, for example, uses data on air quality surrounding a building to control when air is drawn in. In parallel, some solutions focus specifically on monitoring and reporting air quality (see Airthings and OneSky), while others are physical interventions such as paints that absorb pollutants (see Graphenstone’s) and cloths that absorb emissions from construction materials (see cTrap).

Water efficiency

Water efficiency is also a critical focus area in the face of increasing unpredictability and scarcity of water provision, and to reduce the energy required to deliver clean water into buildings. Solutions include digital platforms that monitor water use in buildings and alert users of leaks (such as GUARDIAN and the AI-integrated WINT), physical solutions that reduce W/C water consumption (such as the Encore Cistern that flushes with AC unit wastewater and Propelair with air, or Aguardio’s toilet leak sensor), and those that influence the behaviour of building owners and occupiers (such as Aguardio’s shower sensor). 

Although there is great progress in the development of solutions that help make our buildings smarter and more autonomous, there remains a lag between the pace of technological development and the human training and behaviour changes needed to see successful deployment and utilisation. Motivating tenant engagement and behaviour change still has an important role to play in achieving net zero. UKGBC’s own Operational Buildings Optimisation Learning Labs seek to improve understanding of commercial building systems and encourage collaboration between landlords and tenants over energy efficiency. And there are platforms that exist to support this too, employing techniques like gamification to motivate tenant engagement and behaviour change, such as Hello Energy and CUBE Competition.  

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Conclusion

Despite challenging economic conditions and recent government rollbacks of green policies, it is encouraging to see that opportunity for innovation remains strong across the built environment. Investing in and understanding supply chains, harnessing the power of AI, working in synergy with natural systems, improving the quality and utilisation of data, and harnessing the power of collaboration are all themes that prevailed over 2023. As we move into 2024 and beyond, we remain ever-mindful that no single solution offers a silver bullet to the crises we face. UKGBC will continue to work with members to enable the transformational systems change needed and to help raise awareness and adoption of the impactful solutions that support us in getting there.  

If you know of any innovative solutions or start-ups doing important work to improve the sustainability of the built environment, please encourage them to submit their solution for inclusion in UKGBC’s Solutions Library. You can find out more about UKGBC’s work on Solutions & Innovation here, and to explore collaboration opportunities please email innovation@ukgbc.org. 

Acknowledgments

UKGBC Authors

Emily-Rose Garnett and Lucy Rees

UKGBC Contributors

Smith Mordak, Bradley Nissen, Alex Benstead, Tom Wigg, Joanne Wheeler, Anna Hollyman, Kai Liebetanz, Macarena Cardenas, David Steen, Hannah Giddings, Kerri McCarton and Philip Box.

Solutions and Innovation

At UKGBC we take a collaborative approach to identify sustainability challenges across the built environment and help source and implement the solutions to them.
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Sustainable Innovation Cat Hirst

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Highlighting exemplary and commercially available solutions that address common sustainability challenges across the built environment.
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