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Sustainability in the built environment

By James Gee | September 23, 2022

Working within the built environment, we’re exposed to many of the newest technologies and strategies employed to lower the impact of the buildings around us. Whether embracing nature’s original version of carbon capture or introducing new fuel sources, let’s explore some of the new and exciting ways the built environment is reducing its impact, and assess some of the challenges we’ll face along the way.

The team at Smith Goodfellow have personal interests in sustainability especially, with knowledge in various, wide-ranging fields. This piece is written by James, with sustainable technology being a particular area of interest.

Hydrogen

If there’s a buzzword in the sphere of sustainable fuels, it’s hydrogen. Offering the potential of high-density energy storage which can be used for either electricity through a fuel cell, or burned to act much like a fossil fuel without the emissions of hydrocarbons, hydrogen could be what we’ve been searching for.

As the UK transitions to Net Zero by 2050, those in the built environment share one pressing challenge – how to generate heat. There are many players in this space, including:

  • Direct electric heating (more commonly known as electric storage) which are notoriously expensive to run;
  • Air/ground source heat pumps which are much cheaper to run but currently much more expensive to install than their traditional gas counterparts;
  • District heating systems which can allow for shared heat networks that can decarbonise all at once; and,
  • Hydrogen, the apparent wonder element.

In theory, hydrogen can utilise existing gas heating infrastructure in the UK, and be used in a very similar way to how we use gas, i.e. being burnt on demand at the property. Some gas boilers are even available as ‘hydrogen/hydrogen-mix ready’ right now, in preparation for this change. This could speed up our transition and save investment along the way, as we use the existing pipe network and slowly introduce hydrogen into the gas supply until it’s phased out completely (similar to the increasing amount of ethanol in our petrol with E10 fuel). However, there is an issue with the realities around hydrogen’s origins and how effective it truly is at reducing our carbon emissions.

Much like many parts of the climate crisis, understanding where products and consumables come from is essential to understanding what is and isn’t sustainable. In the case of hydrogen, almost all of the UK’s current hydrogen supply is ‘grey’ hydrogen. This is where methane (or so-called natural gas) undergoes an energy intensive transformation process, which results in a hydrogen product (requiring gas, water and a lot of heat). This process not only requires a lot of energy to perform, but has carbon dioxide and carbon monoxide as direct emissions, making the whole process extremely carbon intensive – this doesn’t solve our climate challenges.

‘Green’ hydrogen, however, is the ultimate aim. This is where hydrogen is created from processing water through hydrolysis (you may be getting secondary school flashbacks), and the whole process is powered by electricity. When this electricity is derived from renewable sources like solar and wind, we class this hydrogen as ‘green’, as it doesn’t emit greenhouse gasses in its production. This could also solve some of the issues we currently have with renewables in the wider power grid, where the sun doesn’t always shine, and the wind doesn’t always blow when we need power or heat. It also may help in situation where renewables vastly over-produce, leading us to waste valuable energy. We would be able to create hydrogen in times when there is excess renewable generation, to be stored and distributed when needed. Although, with the falling price of lithium-ion battery storage (and battery chemistries such as LFP allowing for low degradation and deep cycle charging), hydrogen is becoming a tough sell.

However, we’re seeing more oil and gas producers move into the market promising ‘blue’ hydrogen – sounds high-tech right? This is code for grey hydrogen, which involves gas and a multitude of carbon emissions, but with promise of CCS (Carbon Capture and Storage) at the end. Essentially, the agreement is to not release any carbon into the atmosphere after methane processing, and instead bury the carbon emissions somewhere else. This also negates the dramatic cost savings of renewable generation and leaves us with the same reliance on harmful and unpredictable fossil fuels.

For the built environment, hydrogen allows for an alternative to direct electric heating and heat-pump technologies. But the element itself isn’t the silver bullet. For it to be worthwhile in reducing carbon emissions, it must be paired with zero carbon electricity generation. Whatever the future mix may be, building designers can do their part by ensuring our spaces are as efficient and passive as possible, incorporating energy generation and storage, whilst preparing for a mixture of Net Zero technologies. Those in the hydrogen field must also be abundantly clear in their communications about the way their hydrogen is produced, and the impacts it has on the wider world.

 

CCS (Carbon Capture and Storage)

Carbon capture and storage is the process of either capturing carbon at the point of emission or removing CO2 from the atmosphere retrospectively to the same amount. With the built environment being responsible for such an immense share of the UK’s emissions, it’s on the minds of many of the industry’s leaders.

Currently, CCS isn’t commercially viable, citing technical issues, scaling, the energy draw of the process and the sheer costs involved. The CCC’s 2022 report criticised the UK’s national Net Zero approach as being overly reliant on CCS, saying this approach puts the UK at risk of “taking a more expensive decarbonisation route with lower energy security” – a lose-lose scenario in the wake of current global events. Even on a micro scale, product manufacturers simply cannot be basing their decarbonisation plans on CCS, as even with billions of pounds of investment in the UK alone, wide-scale carbon capture simply isn’t here.

Instead of chasing this endlessly, there is the argument that manufacturers, designers, installers, and everyone across the supply chain should be focusing on eliminating carbon at source and opting for innately low or zero carbon technologies— instead of approaching Net Zero with the same processes and materials as before. With the public sentiment for CCS becoming increasingly negative, and the data showing that it’s been repeatedly overpromised and underdelivered, many are seeing it as little more than cop out from addressing carbon emissions properly. Even when carbon capture does become realistic, still then it must be used as a tool to help rectify past emissions, not as a licence to carry on business-as-usual.

 

Carbon offsetting

As mentioned, most of the built environment’s processes and activities are huge emitters right now, and many do not yet have a clear path to decarbonisation. The whole idea of the Government’s 2050 Net Zero initiative as opposed to simply Zero Carbon is because it will eventually be a numbers game – acknowledging some of the most emission-intensive industries may still be polluting for years to come, so by subtracting carbon from the overall equation we will reach zero. This relies on aforementioned CCS, and carbon offsetting.

Carbon offsetting is mostly just tree planting. Lots and lots of tree planting. In the UK, the Northern Forest is an example of an enormous regional carbon offsetting exercise, with the aim to plant 50 million trees upon completion. Aside from its carbon goals, reforestation is also something which helps to make local landscapes more resilient, more biodiverse and more enjoyable for people to explore. Following our work to assess impact in 2021, we even joined Manchester City of Trees to join this reforesting effort.

Carbon offsetting is a great tool, especially when used locally, to help balance emissions and rejuvenate the world around us. It cannot, however, be seen as another silver bullet to the climate crisis. Especially when deforestation is so rampant globally, we can’t tree plant our way out of 34 billion yearly tonnes of CO2 emissions, and simply resume business as usual. Instead, we should use these initiatives responsibly, as part of a holistic plan to regenerate the environment and reduce our emissions. It will form part of the solution, but it will not be the solution.

 

Looking towards the future

These are just a few of the technologies and approaches we’ll see flourish in the built environment over the next decade, but there are many, many more. One thing which must remain constant however is the honesty and integrity of messaging and communication surrounding them, with the responsibility to tell the full story, and drive change in a responsible way.

To read more about the climate crisis through the lens of communication, read ‘is the climate crisis a communications issue?’, and to hear more about our views on the built environment, look out for editions of Industry Insights, where we discuss new and notable events and trends in the built environment.