Why residential eco-retrofits are failing in the UK

Retrofit projects to make homes more energy efficient are failing, especially when their design is dictated only by financial values, according to the Sustainable Traditional Buildings Alliance (STBA).

It is backing a “Responsible Retrofit” program incorporating health and heritage values and not just financial ones, in order to encourage a new attitude to giving old homes makeovers.

About 25 million British homes were built before 1990 and are in need of retrofits to bring them at least up to modern standards for energy efficiency. And it is generally considered more economic to retrofit the whole house at one go, as I argue in my book the Earthscan Expert Guide to Sustainable Home Refurbishment.

Yet there are many unintended consequences of existing retrofit programs, especially piecemeal ones. They may lead to unhealthy indoor environments, condensation and mould, fabric decay and other problems that affect occupants.

Often programs fail to meet their targets for reducing greenhouse gas emissions and energy use, and in some cases even result in an increase in both of these.

Part of the problem is that there is often not a whole house/building approach when retrofit measures are applied. But even when there is a whole building approach similar consequences can ensue. This is because there are different ideas of what is involved in a whole building retrofit. So what are these different ideas?

Responsible retrofits

An earlier report from the STBA called Responsible Retrofit of Traditional Buildings found that most of the problems that occur with retrofits are at the interfaces between elements, technologies for building processes, or through the interactions between the measures taken, people, and the buildings they occupy, many of which are not fully understood.

This is not just a technical issue. Buildings, and people, behave differently and interact differently depending upon the social, economic and environmental context in which they find themselves.

All of these aspects need to be taken account of. The aim of retrofits should be to look for multiple wins: such as how to improve occupant health, the long-term condition of the building fabric, and make it easy to live in.

To achieve this they need to examine the way thermal energy is conducted through the building and where moisture travels and how it is managed, throughout the year-round weather conditions and patterns of occupancy. This is especially true where different materials meet each other.

When retrofits do fail, it’s not “just because we do not sufficiently understand traditional buildings, or have the wrong approach or the wrong standards or skills”, the STBA says.

“It is because we have an economic and political system which is driving misallocation of finance, land and housing, depletion of natural resources and pollution.”

This is really the reason why The Green Deal programme failed so abysmally, as I have shown before – and why the German equivalent has succeeded.

What values should be incorporated then? The STBA says we need to account for heritage, well-being, community, biodiversity and health – values which, for most people, give meaning to their world more than money does.

But the organisation is pessimistic this can happen without an ethical approach being taken to the allocation of finances for retrofitting. It believes that this demands that the economy and society should “have sustainability and culture at their heart”.

That is why it is issuing a call to rethink the whole approach. It argues:

“The process of retrofit, if carried out correctly, has great potential not only to repair the environment but also to improve people’s lives. Unless we start with the Whole House Advanced/Responsible Retrofit position our efforts will lead to unintended consequences and may be counterproductive even in the most narrowly measured terms.”

To this end the STBA has launched a Responsible Retrofit website, which is full of resources, one of the most useful of which is the Guidance Wheel.

This interactive tool represents over 50 measures that can be used in the refurbishing of the buildings and allows you to explore their interrelationships including the user’s interest, motivation and knowledge about the building:

Since its launch, it has been taken up by several other organisations, including the Society for the Protection of Ancient Buildings and Construction Excellence Wales.

But until it is mainstreamed into the general drive to upgrade the performance of all older buildings, rather than just heritage ones, then piecemeal retrofitting, driven by economics, will prevail in the marketplace, and with it the risk of failure to deliver the desired outcomes.

David Thorpe is the author of:

• Earthscan Expert Guide to Sustainable Home Refurbishment 
• Earthscan Expert Guide to Energy Management in Buildings
• Earthscan Expert Guide to Energy Management in Industry 
• Earthscan Expert Guide to Solar Technology
• The One Planet Life
• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S., UNEP)
• A London Conversation: Business Briefing on using Green Bonds for energy efficiency in buildings

63 ways to cut the global warming impact of cement

NOTE: A version of this article was fist published on The Fifth Estate on 6 December. 

New techniques and substitutes are now available or up-and-coming to reduce the environmental impact of cement production – the third-most polluting industry in terms of greenhouse gas emissions behind chemicals/petrochemicals and iron and steel.

Last month Nature Geoscience journal published research that claimed an average of 42 per cent of greenhouse gas emissions associated with the creation of cement are recouped from the atmosphere once the concrete is in situ.

This is good news, if true, but work is still needed to reduce the carbon footprint of cement in order to prevent disastrous global warming, and the opportunity exists to turn cement from climate change villain to climate change hero by making it carbon negative – that is, absorbing more carbon dioxide from the atmosphere than was used to produce it.

This article examines the nature of cement and concrete, ways to reduce the impact of its present production processes, and novel substitutes and means of production that, if successful at scale, will eradicate greenhouse gas emissions from its lifecycle.

All in all, this adds up to around 63 ways to cut the global warming impact of cement.

What is concrete?

Concrete is made from varying proportions of coarse aggregate bonded with cement that hardens over time. Most concretes used are lime-based concretes made from calcium silicate, such as Portland cement. The main ingredient is limestone or calcium carbonate (CaCO₃).

Portland cement is made by heating the raw materials including the limestone firstly to above 600°C and then to around 1450°C to sinter the materials. This emits carbon dioxide and produces calcium silicate ((CaO)₃·SiO₂). When it is turned into liquid cement with the addition of water and exposed to the air it absorbs carbon dioxide again, to reform into calcium carbonate (CaCO₃), and hardens.

The material is vital to modern construction and ubiquitous; the massive ready-mix concrete industry, the largest segment of the cement market (a staggering 4.3 billion tonnes a year produced), is worth over $100 billion a year.

The global warming impact of cement

Most of the greenhouse gas emissions associated with cement production arise because its production requires very high temperatures, but there are also significant emissions associated with mining and transportation.

Embodied carbon dioxide of cement according to production method.

Source: Specifying Sustainable Concrete from The Concrete Centre.

Existing ways to reduce emissions from cement production

The International Energy Agency (IEA) estimates the global cement industry could save between 28 per cent and 33 per cent of total energy use by the adoption of best practice commercial technologies. So what are these?

1. Heat recovery for efficiency savings

Best practice involves energy efficiency savings in the production and supply chain. These could result in savings of between 60 Mt CO₂/year (at the low end) and 520 Mt CO₂/year, according to the IEA.

One of the most effective techniques is heat recovery and reuse, but this remains relatively unexploited. Waste Heat to Power is one form of heat recovery and reuse. The high temperatures associated with cement production can also be used to generate steam that is then used in steam turbines. This approach has been widely used in China, which hosts over 700 installations in the cement industry.

2. The GreenConcrete LCA

This web-based tool is based on MS-Excel and has been developed to analyse environmental impacts of production of concrete and its constituents (such as cement, aggregates, admixtures, and supplementary cementitious materials).

The tool is not a conventional database of inventory of resources (materials, energy, and water) and emissions from manufacturing that only considers direct impacts, for example, only tailpipe emissions during transportation of concrete materials or emissions from electricity generation.

In GreenConcrete, the supply chain impacts of each process during the production of concrete and its materials are evaluated. This makes it possible to analyse where the savings can be generated the most and what technological improvements to make.

Primary energy used (in the form of fuel and electricity) throughout the production and transportation processes is one of the main environmental impacts analysed as part of the study.

Materials substitution, for example the addition of wastes and geo-polymers to clinker, can reduce CO₂ emissions from cement manufacture and save energy.

Clinker may be blended with alternative materials like blast furnace slag, fly ash from coal fired power plants and natural pozzolans. Use of granulated slag in Portland cement may increase energy use in the steel industry, but can reduce both energy consumption and CO₂ emissions during cement production by about 40 per cent.

3 to 53. Over 50 energy efficiency opportunities

This EnergyStar guide for energy and plant managers, Energy efficiency improvement and cost saving opportunities for cement making, outlines over 50 specific energy efficiency opportunities for all stages of the different production processes of different types of cement.

This includes over fifty changes to production methods such as: using high-efficiency roller mills, energy management and process controls, kiln shell heat loss reduction, use of waste fuels, conversion to pre-heating for the kiln, pre-calciner kilns, better maintenance and optimisation of parts and systems, oxygen enrichment, high efficiency motors and variable speed drives, using steel slag in kiln and much more.

54. Recycling and reusing

Savings can also be made at the end of life of a concrete structure. Currently only 50 per cent of concrete is recycled for use in new building projects (compared to up to 99 per cent for structural steel).

Down-cycling does help to reduce the use of aggregates, but does not help to reduce the supply of materials needed for new concrete.

Alternatives to Portland cement

There are also several candidates for substitutes for Portland cement that have less of an impact on global warming.

“Limestone-free cements can be achieved through chemical ‘activation’ of by-product materials or by producing an array of cementitious compounds based on magnesium oxide,” according to Jenny Burridge, the head of structural engineering at The Concrete Centre, UK. Here are the main ones:

55. Magnesium silicates

This involves the accelerated carbonation of magnesium silicates instead of calcium carbonates under high temperature and pressure, with the resulting carbonates then heated at low temperatures to produce magnesium oxide, with the CO₂ generated being recycled back in the process.

The use of magnesium silicates eliminates the CO₂ emissions from raw materials processing. In addition, the low temperatures required allow the use of fuels with low energy content or carbon intensity (biomass), thus potentially further reducing carbon emissions.

As with Portland cement, production of the carbonates absorbs carbon dioxide by carbonating part of the manufactured magnesium oxide using atmospheric/ industrial CO₂.

In recent years it was hoped that the claim of manufacturers Novacem (a spin-out company from Imperial College London) – that making one tonne of cement using this method absorbs up to 100kg more CO₂ than it emits, making it a carbon-negative product – could revolutionise the industry. However, there have been problems associated with trying to scale up production and the company became insolvent in 2013.

56. Calera

Calera’s process involves the capture of raw flue CO₂ gas from industrial sources and converting it into calcium carbonate cement-based building materials. By converting the gas into a solid form of calcium carbonate it permanently sequesters the CO₂.

Commercial demonstrations have included the capture of flue gas from power plants and burning coal, without concentrating the CO₂. The flue gas is contacted in a scrubber with an aqueous alkaline solution that effectively removes the CO₂ and a calcium source that results in the formation of the special calcium carbonate product that is then dried to a free flowing powder.

It requires sources both of alkalinity and calcium. Some industrial waste streams contain both, like calcium hydroxide (Ca(OH)2). Another option is separate streams, one for alkalinity, such as sodium hydroxide (NaOH), and one for calcium, like calcium chloride, which can be naturally occurring or found in the waste streams of existing chemical processes.

The result is a high strength material that can be used without any other cement or binder system to make concrete products from countertops, plant holders and benches to fibre cement board sheets on a commercial line, exceeding strength requirements but of a lighter weight than many existing cement board products.

57. SOLIDIA

SOLIDIA cement is a related product and process that cures concrete with carbon dioxide, say, from flue gases, and is currently at commercialisation stage. It requires less limestone as a result and can therefore be fired at lower kiln temperatures. It requires less energy and generates around 30 per cent less greenhouse gases than ordinary Portland cement.

58. Celitement

Celitement is a cement substitute produced at temperatures below 300°C under a process developed by the German Karlsruhe Institute of Technology KIT. It will therefore require less energy and emit fewer greenhouse gases.

Celitement is calcium hydrosilicate, a raw material already containing calcium (CaO) and silicon (SiO₂), though in the wrong ratio. It must be processed using an autoclave under saturated steam conditions, grinding and the addition of water.

All of this emits around 50 per cent less carbon dioxide than Portland Cement. But it is still at the R&D stage.

59. Fly ash cement

Alkali activated and “geopolymer” cements gain their strength from chemical reactions between a source of alkali (soluble base activator) and aluminate-rich materials.

The source of the aluminate-rich materials will be an otherwise waste product – fly ash, municipal solid waste incinerator ash (MSWIA), metakaolin, blast furnace slag, steel slag or other slags, or other alumina-rich materials.

They tend to have lower embodied energy/carbon footprints than Portland cements (up to 80-90 per cent, but this is dependent on the source of the aluminate-rich material).

Production is now covered by a standard: PAS 8820:2016 Construction materials.

60. Ferrock

Created by David Stone, it is composed partly of iron dust reclaimed from steel mills and currently sent to landfill. Stone has patented the name Ferrock and formed a company, IronKast, which is in the early stages of commercialising the patent with pilot implementations in marine environments being tested and benchmarked by the University of Arizona.

It emits no carbon dioxide during production and, in order to cure it, as with Portland cement, carbon dioxide is required as a catalyst thereby making it carbon negative.

When CO₂ dissolves into water it forms carbonic acid. If iron dust is present it combines with carbonate molecules and precipitates back out of solution as solid iron carbonate. The resultant material has a greater compressive strength than mortar made with Portland cement.

However, because of the limited availability of the iron dust, it will never completely replace all uses of Portland cement.

61. Hempcrete

Another substitute for concrete is Hempcrete, which is made from hemp and lime. Hemp, when growing, absorbs atmospheric carbon dioxide. Lime, when applied this way, also absorbs atmospheric carbon dioxide, making the material carbon negative.

While not having the structural strength of concrete (its typical compressive strength is around 1MPa, over 20 times lower than low grade concrete and its density is 15 per cent that of traditional concrete), with a k-value of between 0.12 and 0.13 W/mK, it offers some insulation value.

It can be used in many situations where concrete is currently used.

It is of interest also because of its breathability, which lends it to use with other national building materials to create buildings that have a pleasant internal atmosphere that does not suffer from damp or condensation.

62. Aether

Aether is a partnership by Lafarge, a world leader in building materials, with two technical centres, BRE (UK) and the Institute of Ceramics and Building Materials (Poland).

Technically, this is a Belite-Calcium Sulfo-Aluminate-Ferrite compound. Trials found that Aether generates 20 to 30 per cent less CO₂ per tonne of cement than pure Portland cement (CEM (I) type) and had a compressive strength similar to Portland cement. There is a European standard now underway.

This is still at the R&D stage however; the key problem is that it hydrates slowly.

Summary so far

In terms of embodied CO₂ alternative cements are showing good promise, but there is a lack of experience, a lack of codes and standards, and some concerns about raw material availability and about durability.

A study of the recent start-up attempts in this area, Towards low-carbon alternatives for OPC, concluded that the technologies are still at an early stage: “High-end cement science using new analytical techniques and modelling is just beginning and marks a methodological breakthrough”.

It advocates “collaboration between interested industry partners and basic research institutes and resources for long-term research projects as a necessary precondition for the progress of radical inventions”.

This is exactly the approach being taken by LEILAC, a new collaboration between European and Australian partners.

63. LEILAC

The LEILAC (Low Emissions Intensity Lime And Cement) project is trialling a new type of carbon capture technology called Direct Separation. To this end it is about to build and operate a pilot plant at the HeidelbergCement plant in Lixhe, Belgium.

Diagram of the LEILAC (Low Emissions Intensity Lime And Cement) project with carbon capture technology.

This aims to capture about 60 per cent of total CO₂ emissions from both industries without significant energy or capital penalty, with throughputs of up to 240 tonnes of cement per day and demonstrate that the technology works sufficiently robustly to begin scale-up planning.

The technology is already proven at commercial scale for processing magnesite in Australia – a similar ore to limestone, albeit at lower temperatures (760°C versus 950°C exhaust temperatures).

The company operating this, Calix, is lead partner in the project. It has already partially calcined limestone, albeit to around 70 per cent in a 22-metre long tube with no pre-heating. It uses the Catalytic Steam Calcination of limestone, dolomite and magnesite for cement and building products.

The project has received €12m (AU$17.3m) in grant funding as part of the European Union’s Horizons 2020 program. HeidelbergCement, CEMEX, Tarmac, Lhoist, Amec Foster Wheeler, Calix Limited, ECN, Imperial College, PSE, Quantis, and the Carbon Trust are all working to apply this critical technology to the cement and lime industries.

All these partners recognise that the long-term future of the cement and lime industries, which are both vital for many aspects of the European economy, hinge upon a reduction in their CO₂ emissions.

The separate elements of capture, transport and storage of carbon dioxide have all been demonstrated, but integrating them into a complete CCS process and bringing costs down remains a challenge.

There are two large projects currently working in Europe, at Sleipner (operating since 1996) and Snøhvit (operating since 2008), capturing and storing around 1.7 million tonnes of CO₂.

However, the technology has not been applied to the cement nor lime industries, as traditional methods of capturing the CO₂ are either too complex or expensive.

The new trial aims to do just this by beginning a full Front End Engineering Design (FEED) phase. Results should be available in 2020.


When integrated into new plants, or retrofitted into existing plants that are fired with biomass or by waste combustion, and using current best practice as outlined above, by using “Direct Separation” technology the total CO₂ emissions of cement production would be reduced by more than 85 per cent compared to conventional fossil fuel fired lime and cement plants, without significant operating issues, energy or capital penalty.

If to this was added the figure of 42 per cent – of greenhouse gas emissions associated with the creation of cement using conventional means that are now known to be absorbed by concrete after its creation – then this would mean that conventional concrete would actually be potentially carbon negative.

That is surely a dream worth pursuing.

David Thorpe is the author of:

• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S. UNEP, 2016)
• A London Conversation: Business Briefing on Green Bonds (The Fifth Estate, 2015)
• The One Planet Life (Introduction: Jane Davidson. Routledge, 2015)
• Earthscan Expert Guide to Energy Management in Buildings (Earthscan, 2013)
• Earthscan Expert Guide to Energy Management in Industry (Earthscan, 2013)
• Earthscan Expert Guide to Solar Technology (Earthscan, 2011)
• Earthscan Expert Guide to Sustainable Home Refurbishment (Earthscan, 2010)

Wanted: a serious business model for eco-retrofitting homes

[NOTE: A version of this article appeared on The Fifth Estate on 29 November.]

A new approach is needed to retrofit the UK’s housing stock to allow it to contribute to a cost-effective decarbonisation strategy, according to a report published by the Energy Technologies Institute.

But the report does not make it really clear what this approach might be.

Although deep retrofits of houses for energy efficiency are technically feasible, as detailed in my book the Earthscan Expert Guide to Sustainable Home Refurbishment, at present doing it to the proper standard might cost around the same as rebuilding the entire UK housing stock.

New homes built to modern UK Building Regulations standards will cost approximately half as much to heat as a Victorian home, according to the British NHBC Foundation. These new or refurbished homes mean reduced bills for heating, hot water and electricity bills, due to better standards of insulation, draught-proofing and improved airtightness, double glazing and efficient controls (programmer, room thermostats and thermostatic radiator valves).

The difference in heating costs between a new and Victorian home. Source: NHBC

Housing Retrofits – A New Start, written by the ETI’s chief engineer Andrew Haslett, looks at the role of housing retrofitting when seeking to tackle the 20 per cent of emissions that comes from heating the UK’s 28 million homes.

Its conclusions come from a two-stage process. The ETI first identified two particular retrofitting approaches that were the most cost-effective in terms of getting the most from time and materials by industrialising the planning and execution of projects. They followed this up by testing them out on five typical UK dwellings (terrace, semi-detached, detached) built from pre-1919 to post-1980, to work out what might be deliverable in the real world. Here are the results:

Retrofits were successfully completed on four of the houses, with gas usage reduced by 30-50 per cent. But the costs ranged from £32,000 to £77,000. The experience led the team to conclude that proper investment in supply chain and training might reduce this by about half to £17,000 to £31,000.

The incentive gap

That’s still a lot. So how do we persuade someone to spend the money? The report highlights that most consumers are not motivated to spend money on efficiency measures because efficiency savings are a very weak driver. That is the “incentive gap”.

Instead, the report recommends that improved comfort, health and amenity should be the main incentive to fill this gap, with saving money on bills as a secondary benefit.

Meanwhile, at the back end, finding savings in the supply chain by scaling up manufacture and supply, and rewards to investors or installers, and/or legally binding targets for carbon savings (carrots and sticks), would seriously help, both in the social and private sectors.

The ETI has made a video about the project:



But the route to market is still fuzzy.

The need for investment

UK Government spending on grants for home energy efficiency is currently languishing at a 20-year low.

This year has seen a massive fall in the number of households helped by government to become more efficient, with the annual number of major energy efficiency measures installed in homes declining by 80 per cent from 1.74 million to 340,000 between the height of delivery in 2012 and 2015, according to the Association for the Conservation of Energy.

The government seems to lack any sense of the value of energy efficiency compared to investing in large scale energy projects. The ETI reckons that with carbon prices at such a modest level one way to improve housing efficiency lies in more effort to tackle the approximately four million hard to treat cavity walls across the UK. But governments have been trying for years to incentivise this and not even all the “easy wins” have been fixed.

Wanted: a serious model

Although the ETI wants to make eco-retrofits “an integral part of improving the amenity and value of the dwellings”, rather than seeing them as a series of independent measures, it does not present a financial model for doing this.

The only hope it offers is a vague one for “a new kind of service provider (integrator)” to replace existing energy providers, on a franchised basis (local teams), “that aims for a much higher level of service provision, starting with existing energy supplies”.

Such companies would have “a plan for the decarbonisation of supply of each dwelling” but “only if a market environment can be created over the next five years”.

Given the current preoccupations of the UK Government – Brexit – and the lack of any mention of climate change or social care in the government’s budgetary spending plans announced last week, that’s a big ask.

It’s not as if the ETI is asking for a lot of cash compared to the scale of the task. It says: “£10 billion of private and public funds over the next 10 years would provide a platform that would enable investment of roughly £100bn out to 2050″.

Financial Disclosure

The incentive gap is to be addressed by yet another report, soon to be released, this time from the UK Financial Stability Board’s Task Force on Climate-related Financial Disclosures.

It will contain their first set of recommendations about how to help close the gap between the climate/sustainability world and traditional finance thinking.

It will say that all infrastructure projects – not just housing retrofits – have a climate-related element to them, be that energy efficiency (mitigation), resilience against adverse weather events (adaptation) or others.

Therefore policy to encourage the reporting of more information on these topics will help to bring more visibility to the benefits.

And standardising how this information is reported would ensure that it can be used for investor analysis, enabling investors to set targets, and the creation of more products that are attractive to investors.

Well that’s what the Investor Confidence Project is doing. I wonder if the FSB knows about it.

The ETI is conducting important research. What they have done is expose the difficulty of the task but they have only begun to chart a path to accomplishing it.

David Thorpe is the author of:

• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S. UNEP, 2016)
• A London Conversation: Business Briefing on Green Bonds (The Fifth Estate, 2015)
• The One Planet Life (Introduction: Jane Davidson. Routledge, 2015)
• Earthscan Expert Guide to Energy Management in Buildings (Earthscan, 2013)
• Earthscan Expert Guide to Energy Management in Industry (Earthscan, 2013)
• Earthscan Expert Guide to Solar Technology (Earthscan, 2011)
• Earthscan Expert Guide to Sustainable Home Refurbishment (Earthscan, 2010)

COP22 put built environment at the forefront of climate change action

Note: This post was originally published on The Fifth Estate on 23 November 2016. 

Cities and local governments were especially evident at the Low-Emissions Solutions Conference held during last week’s COP22 global climate talks in Marrakech, Morocco, where a Handbook on creating dynamic local markets for Energy Efficient Buildings was launched.

The handbook uses a business-led approach piloted in 10 cities over the last four years to develop and implement action plans on energy efficiency in buildings.

Multi-stakeholder relationships in the building value chain and how they need to come together to promote energy efficiency in buildings. Source: WBCSD (2015), adapted from Energy Efficiency in Buildings, Business Realities and Opportunities, Facts and Trends.

The handbook goes through the steps involved and how to bring together the many different groups that comprise the buildings sector.

A key example from the handbook is taken from Poland, a country not normally noted for its action on climate change. It describes how a multi-stakeholder partnership set up in 2014 has, by November 2016, already set up a residential buildings energy efficiency financing facility of €200 million (AU$287m), produced a benchmarking report on operation costs in commercial buildings, and created a platform for public-private dialogue and action.

It is part of an initiative called EEB Amplify, launched on COP22’s Buildings and Cities Day with the aim of scaling up the Energy Efficiency in Buildings program from 10 cities to 50 by 2020. ICLEI – Local Governments for Sustainability is currently working with 1500 cities across the world.

EEB Amplify is a partnership with the World Business Council for Sustainable Development (WBCSD) and Climate-KIC in Europe, the US Green Building Council and US Business Council for Sustainable Development, and the Indian Green Building Council. Its expansion will begin in 2017 and aims to include 50 cities by 2020.

Why different stakeholders should get involved in an energy efficiency market engagement, in what capacity, and what they stand to gain. Source: Extract from Energy Efficiency Market Report 2015, IEA adapted from IEA (2014), Capturing the Multiple Benefits of Energy Efficiency, OECD/IEA, Paris.

It’s time to get down to business

COP22 was all about implementation. There was a shared feeling that the Paris Agreement and the adoption of the Sustainable Development Goals have created an irreversible and irresistible pathway to a low-carbon world and now, despite what has happened in America, the task is just to get on with it.

On display at the conference were materials, construction innovation, technologies for energy efficiency, adaptation and resilience, and sustainable mobility across electric and fuel cell vehicles.

No new fossil fuel infrastructure

NGO and government leaders spoke at a press conference about how subnational governments and major cities around the world – including in the US and Canada – are adopting No New Fossil Fuel Infrastructure policies and pledges.

Cities across the Western US who have signed up to the No New Fossil Fuel Infrastructure policy include Portland, Oregon and Vancouver, and uptake is accelerating.

100 per cent renewable energy

Many cities and governments signalled an intention to move cities and regions away from all fossil fuel export infrastructure and towards 100 per cent renewable energy. Many already are.

US Secretary of State John Kerry announced the Obama Administration’s plan for deep decarbonisation, even though the Trump administration could well undo it.

While acknowledging the uncertainty Trump’s win creates, he predicted that markets would continue to drive the transition to clean energy sources for economic reasons, and that the question was whether it would happen sufficiently fast to avoid catastrophic climate damage.

“The US plan for deep decarbonisation Secretary Kerry unveiled today is a welcome recognition of the need for urgent action, however, it does not go nearly far enough,” observed Daphne Wysham, director of the climate and energy program at the Center for Sustainable Economy.

So city representatives joined 47 governments forming the Climate Vulnerable Forum, business and civil society including from Morocco, Ethiopia and Costa Rica, the City of Oslo, the Australian Capital Territory Government, Sumba Islands and corporations like Mars and IKEA to talk about the movement towards 100 per cent renewable energy cities.

COP22 President Salaheddine Mezouar said that “renewable energies do not only mitigate our impact on climate change but open the way to new models of sustainable development with new investments, new industries and new jobs”.

Sustainable cities and built environments

The COP22 Low-Emissions Solutions Conference established four work streams:

1. National and regional low-carbon strategies: mid-century strategies, deep decarbonisation pathways, and implementation at national, regional and local scales; and solutions and innovations spotlight
2. Information and communications technologies: the contribution of ICT to climate action in other sectors; and innovative approaches to raising commitments towards climate action
3. Sustainable cities and built environments: local climate action – strategies and implementation; and smart low-carbon and sustainable cities
4. Low-carbon transport: introduction to mobility challenges and innovation in the transport sector; and electric and hydrogen mobility.

The built environment is at the heart of all of of these work streams.

Following the conference, Gino Van Begin, secretary general of ICLEI, called upon all stakeholders – business, the research community and all levels of government – to get together with local governments to “implement and take up new technologies that facilitate low emission, resilient development” and to “allow innovation to happen and to be effectively applied”.

Only by working together will they, and by definition, the world, “build a strong architecture needed to support implementation of the Paris Agreement”, he said.

Peter Bakker, president and CEO of the WBCSD echoed this, saying the conference showed “how business, government, academia, cities and other experts are already delivering the solutions that will define future competitiveness in the low-carbon economy”.

Cities100

Cities100 was another highlight of the cities day at COP22. It showcased leading solutions to urban climate challenges in 10 sectors, ranging from solid waste management to transportation, and, for the first time, solutions that address the nexus of climate change and social equity. Amongst the examples in Cities100 were:

• Guang­zhou, China: planning for an increasing population and rising demand for energy using a multi-sector, low carbon plan for green growth targeting infrastructure and buildings
• Kampala, Uganda: instituting energy efficiency and sustainability in all its operations to make itself an example for other African cities.
• Taoyuan, Taiwan: which has a development plan targeting lifestyle changes and the creation of a renewable energy industry.
• New York City, US: its Hous­ing Au­thor­ity has a building retrofit strategy to reduce CO2 emissions, heating costs and make sure that residents in affordable housing have resilient homes.
• Auckland, New Zealand: has set up a revolving fund to enable the city to invest money generated from municipal energy-saving projects into further energy-saving improvements.

C40 chair and Rio de Janeiro mayor Eduardo Paes gave a keynote address at the Sustainable Innovation Forum, which highlighted the importance of mayors and cities in tackling climate change, saying that cities are taking bold actions, but much more needs to be done, including a “coordinated collaboration between all levels of society”.

He talked about how carbon intensive and traditional businesses needed to be reinvented because they “will not have a place in a world facing climate change”, calling this “a great economic opportunity”.

“In the next 15 years, the world is expected to invest around USD $90 trillion in infrastructure. Much of that will happen in cities … Municipal governments cannot leverage those resources alone,” he said.

Climate finance

According to C40’s research, urban policy decisions made in the next four years alone could lock-in almost a third of the remaining global safe carbon budget. This is why C40 supports its member cities in developing targets and climate action plans that are aligned with a 1.5 degree pathway.

C40’s Climate Finance Facility, now in its pilot phase, will support cities in low and middle-income countries in preparing climate change projects to attract investments.

C40’s demands for municipal infrastructure finance.

At the end of November, at the C40 bi-annual Summit in Mexico City, C40 will adopt a new four year business plan with the ambition of the Paris Agreement at its centre.

No to Trump

The 200 countries attending the COP22 conference were united in the face of Donald Trump’s campaign threat to quit the Paris accord on climate change.

“No one country, no one man, no one person can control the outcome of the destiny that we all see as part of the writing on the wall that climate change is real, we need to act and we are going to do everything we can so I definitely think that the speeches over the past several days had that impact and effect on us as a civil society and over other countries as well,” concluded Tina Johnson, policy director at the US Climate Network.

The Marrakech Proclamation, issued at the conclusion of the conference, serves as a message of solidarity against Trump’s threat. The Proclamation contains a resolution to hammer out a rulebook by 2018, and this is its concluding sentence:

“As we now turn towards implementation and action, we reiterate our resolve to inspire solidarity, hope and opportunity for current and future generations.”

David Thorpe is the author of:

• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S. UNEP, 2016)
• A London Conversation: Business Briefing on Green Bonds (The Fifth Estate, 2015)
• The One Planet Life (Introduction: Jane Davidson. Routledge, 2015)
• Earthscan Expert Guide to Energy Management in Buildings (Earthscan, 2013)
• Earthscan Expert Guide to Energy Management in Industry (Earthscan, 2013)
• Earthscan Expert Guide to Solar Technology (Earthscan, 2011)
• Earthscan Expert Guide to Sustainable Home Refurbishment (Earthscan, 2010)

How changing building shape and form can slash energy use

[Note: This post was originally published on The Fifth Estate website on 15 November 2016]

New guidance has just been issued to help architects, developers and designers understand more about how the shape and form of a building affects heat loss, so they can reduce the energy consumption of new buildings at little or no extra cost.

This guidance is contained in a new report published by the research arm of the British National House-Building Council, called The challenge of shape and form. The mission of the NHBC is to raise the construction standards of new homes and provide guaranteed protection for homebuyers.

Much of the focus on improving the energy efficiency of buildings has to date been in connection with building fabric, insulation and new technology, but their shape and form can be just as important. By paying attention to this, developers can add value to homes and gain a competitive edge.

Mathematical models are used to predict the energy consumption of buildings. These models correctly reflect the importance of the form factor. The form factor is a measure of the compactness of a building in the form of a ratio of the external area of the building to the floor area. In short:

Heat Loss Form Factor = Heat Loss Area / Treated Floor Area

This ratio can be anything between 0.5 and five. A lower number indicates a more compact, efficient building.

The Form Factor for different building styles and sizes. 

Passivhaus buildings aim to achieve three or less. Once the form factor is over three, achieving the Passivhaus Standard efficiently becomes more challenging.

The early design choices, such as how many storeys a building has, what shape the plan takes, the form and massing, all impact directly on the building energy efficiency.

A building can have a fairly simple massing, but if it has a lot of recesses or protrusions in the thermal envelope, the surface areas soon add up. Less (thermal envelope) surface area means less surface area for heat to escape through. This is shown in the following diagrams.

How changing a building's shape alters its surface area.

Form factor and insulation

The form factor has an effect on the amount of insulation needed to achieve the same U-value (measure of heat loss: – the 2013 UK building regulations have limiting U-values of 0.2 W/(m2.K) for a roof and 0.3 W/(m2.K) for walls). If a large compact block of flats had a form factor of 1.0, an average U-value of only 0.28 W/(m2.K) would be required.

The following figures illustrate this:

Heat loss area and U-values have a linear relationship. If the heat loss area of one option is twice that of another option, the insulation will need to be twice as thick!

The problem in Britain

In the UK, the energy and carbon requirements of building regulations do not explicitly give credit for housing designs with lower heat loss areas or more efficient shapes that will reduce heating costs for the building occupants.

The UK’s national calculation methodology, the Standard Assessment Procedure, does give appropriate weight to the form factor in calculating heat loss. But when the basic results from SAP model are fed into the buildings regulations compliance methodology, which follows, the benefits of form factor do not register.

The current Building Regulations in the UK are therefore unable to provide an incentive for industry to design and build homes that have a more efficient type and shape.

The NHBC says designers who focus solely on building regulations compliance may not even realise that they can reduce the energy consumption of homes by changing the form factor.

Doing so can be a low-cost or no-cost measure. The NHBC is calling on the government to consider ways of encouraging designers and developers to take advantage of this effect.

The effect of form and shape

Even though the form may be compact, the building can still be architecturally interesting and provide better comfort conditions for occupants. It need not have to lead to bland or monotonous housing designs.

The guide discusses how the most inefficient design features can often be avoided or replaced by alternatives that are still architecturally interesting. Many designs can provide better comfort conditions for the residents as well.

The NHBC hopes that form factor will gain a “currency” of its own, and will be included among the key parameters that are tracked and discussed as a housing development design evolves.

This is already the case in countries where alternative design approaches are popular; the Passivhaus standard, for example, lists efficient building shape as one of the five key design considerations when planning a new energy-efficient building.

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David Thorpe is the author of:

• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S. UNEP, 2016)
• A London Conversation: Business Briefing on Green Bonds (The Fifth Estate, 2015)
• The One Planet Life (Introduction: Jane Davidson. Routledge, 2015)
• Earthscan Expert Guide to Energy Management in Buildings (Earthscan, 2013)
• Earthscan Expert Guide to Energy Management in Industry (Earthscan, 2013)
• Earthscan Expert Guide to Solar Technology (Earthscan, 2011)
• Earthscan Expert Guide to Sustainable Home Refurbishment (Earthscan, 2010)

UNEP backs Passivhaus to help meet climate targets

[This post originally appeared on The Fifth Estate website on 9 November.]

As the latest round of global climate talks begins, the UN Environment Programme is calling on nations to ramp up their action to reduce greenhouse gas emissions and is explicitly backing the use of the Passivhaus Standard to reduce emissions from buildings.

Thermal image showing how a Passivhaus refurbishment/makeover of a terraced home (the blue one) means it radiates (loses) no heat compared to its neighbours (red and yellow - meaning they are radiating heat. The more red, the more heat is being lost).

Delegates in Marrakesh for yet another climate conference, the 2016 UN Conference of the Parties (COP22), have been studying a report by UNEP on what the world needs to do to meet the requirements of the Paris Agreement and halt dangerous global warming.

COP22 is about following up the just-ratified Paris Agreement. The agreement marks a turning point in the history of the world, establishing both the commitment and the framework for dealing with climate change. COP22 is about fleshing out the detail, and there is a great deal of detail to be fleshed out.

The Intended Nationally Determined Contributions from COP21 form the basis of the Paris Agreement; they are the pledges that each country laid out at year’s negotiations, showing their contribution to tackling climate. But these presently fall well short of achieving COP21’s “well below 2°C” temperature goal.

The Emissions Gap Report

Just in advance of the conference the UNEP issued its “Emissions Gap Report“, which notes the “troubling paradox at the heart of climate policy”.

Erik Solheim

In the words of Erik Solheim, the head of the program, the paradox is that “on the one hand nobody can doubt the historic success of the Paris Agreement, but on the other hand everybody willing to look can already see the impact of our changing climate”.

(Everybody, that is, apart from the Republicans in the US who elected Donald Trump and his cronies. But that is another story.)

This report estimates that we are actually on track for global warming of up to 3.4°C – way over the target. The current commitments made by nations “will reduce emissions by no more than a third of the levels required by 2030 to avert disaster”, he says.

“So, we must take urgent action. If we don’t, we will mourn the loss of biodiversity and natural resources. We will regret the economic fallout. But most of all we will grieve over the avoidable human tragedy.”

Global greenhouse gas emissions continue to grow. UNEP is calling for accelerated efforts now, prior to 2020, and for nations to increase their ambitions in their INDCs.

“Pathways for staying well below 2°C and 1.5°C require deep emission reductions after, and preferably also before 2020, and lower levels of emissions in 2030 than earlier assessed 2°C pathways,” the report says.

The report does identify where solutions are available that can deliver low-cost emission reductions at scale, including the acceleration of energy efficiency.

Much has been said, including by myself, about the effect on emissions by actors who are not nations, such as cities, regions and companies. It’s possible, the report notes, that these could reduce emissions in 2020 and 2030 by a few additional gigatonnes, but it is difficult to assess the overlap with INDCs because these are not usually detailed enough and non-state actions can overlap or mutually reinforce each other.

The importance of energy efficiency

The report emphasises that ambitious action on energy efficiency is urgent. Well-documented opportunities exist to strengthen national policies on energy efficiency.

Studies based on the Fourth Assessment Report of the Intergovernmental Panel on Climate Change show that for a cost range of between US$20 and $100 per tonne of carbon dioxide, 5.9 gigatonnes of emissions could be saved from buildings, 4.1 for industry and 2.1 for transport by 2030. These estimates are conservative and the real potential in each sector is likely to be bigger.

A more recent analysis by the International Energy Agency indicates that the cumulative direct and indirect emissions estimates to 2035 are 30 gigatonnes for buildings, 22 for industry and 12 for transport.

The two studies are not comparable due to differences in approaches, but together illustrate the significant potential in the three sectors.

Improving energy efficiency also offers many other benefits like reduced air pollution and local employment.

It is an integral part of Sustainable Development Goal 7, which aims to “ensure access to affordable, reliable, sustainable and modern energy for all”.

The energy efficiency target is to double the global rate of improvement in energy efficiency by 2030, from 1.3 per cent per year to 2.6 per cent. Achieving this goal will be important for achieving many of the other goals:

• Building energy efficiency will be increased by ratcheting up the ambition of energy codes, and increasing monitoring and enforcement of building regulations with the use of energy performance certification and with encouragement to create highly efficient buildings.

• Industrial energy efficiency will be helped the more that companies introduce energy management by adopting ISO 50001 an energy performance monitoring. Energy performance standards need to be enforced for all industrial equipment.

• Transport energy efficiency is improved by the adoption of vehicle fuel economy standards and electric mobility for passenger transport. For freight movements sustainable logistics can be deployed.

There is a huge role for energy service companies to offer these services.

All of these efficiency savings can be encouraged by planning policy. For example:

• Successful zoning can reduce the need to travel, and neighbourhood layouts can reduce the need for heating or cooling.

• Spatial planning can help to improve transit options, increase and co-locate employment and residential densities, and increase the amount of green spaces.

• Heating, cooling and electrical energy services can also be more efficiently delivered at a neighbourhood scale than at a building scale, with distributed renewable or low-carbon energy supplied by local energy service companies.

The Passivhaus standard

The report explicitly advocates the adoption of the Passivhaus standard. Passivhaus, originating in Germany, is primarily a tough quality assurance standard, which demands great attention to detail during the design and construction process to achieve certification.

Key to it is a target that annual final energy use for heating and cooling should not exceed 15 kilowatt hours a square metre a year.

The report says that the global floor area covered by Passivhaus buildings has grown from 10 million sq m in 2010 to 46 million sq m in 2016, with most activity occurring in Europe.

And importantly, it says the price for new Passivhaus buildings in several countries is comparable to standard construction costs.

Initially developed for mid and northern European climates, Passivhaus has been proven to work extremely well in hot climates too. High levels of airtightness and insulation work equally well in protecting buildings from overheating provided there is adequate solar shading.

Controlled mechanical ventilation allows options to pre-cool or pre-heat the supply air and also to humidify or dehumidify the ambient air depending on the relative humidity. In combination these strategies are capable of significantly buffering the daytime temperature swing.

Conventional cross ventilation through open windows and night purge ventilation strategies may also be used as part of the Passivhaus cooling concept when appropriate, such as during the cooler evening of a hot day.

In order to achieve the Passivehaus standard in hot countries, the outer wall must have a U-value between 0.20-0.45 W/m2K.

Depending on the heat-insulating properties of the loadbearing outer walls and on the thermal conductivity of the insulation material used, it may be necessary to install an external thermal insulation system of up to 30cm thickness.

Modern external thermal insulation composite systems based on mineral raw materials combine the best insulating properties with ease of handling. Compared to conventional insulation systems, the additional expense pays off after only a few years.

In climatic regions where the daytime temperature does not drop low enough to purge the accumulated heat gains from the building at night there will be a residual cooling load.

In such cases the Passivhaus standard permits 15 kWh/m2.yr of cooling energy to be used. A small cooling load has proven to be sufficient in almost all cases because the Passivhaus concept is highly effective in reducing unwanted heat gains.

The blower door test is used to detect leaks in the building envelope. The smaller the measured value, the higher the airtightness. Passive houses in hot countries require a value =< 1.0. This means that during the measurement at most 100 per cent of the indoor air volume is allowed to escape through leaky spots within one hour. Experience has shown that values between 0.3 and 0.4 are attainable.

Passivhaus principles can also be applied to refurbishment of existing buildings and achieve impressive results. In the UK there are many examples of ultra-low energy, low carbon retrofits.

At the same time, the Passivhaus Institut has launched a Passivhaus standard for refurbishment projects, known as “EnerPHit”, covering a range of property types, including tower blocks, terraced houses and community centres.

Given that costs are around the same as for conventional buildings but energy costs of using the building are drastically reduced, why are they not more widely adopted?

The main reasons are the lack of ambition in building codes, the lack of awareness, trained construction workers and appropriate monitoring. For the aims of the Paris Agreement to be realised this is just one opportunity that needs to be grasped.

Since the US election, the need to grasp these opportunities has become even more urgent.

David Thorpe is the author of:

• Best Practices and Case Studies for Industrial Energy Efficiency Improvement (with Oung, K. and Fawkes, S. UNEP, 2016)
• A London Conversation: Business Briefing on Green Bonds (The Fifth Estate, 2015)
• The One Planet Life (Introduction: Jane Davidson. Routledge, 2015)
• Earthscan Expert Guide to Energy Management in Buildings (Earthscan, 2013)
• Earthscan Expert Guide to Energy Management in Industry (Earthscan, 2013)
• Earthscan Expert Guide to Solar Technology (Earthscan, 2011)
• Earthscan Expert Guide to Sustainable Home Refurbishment (Earthscan, 2010)