Imagine a six year-old spending the day building sandcastles and exploring the rock pools on a sun-drenched Cornish beach… and then spending the night unable to sleep because of the pain from the sunburn on his back. That’s my memory of 1976 (that and a very long car journey fighting with my brother in the back of a Reliant Robin), the last time we had weather in the UK as good as we’ve had this year. But, so the family legend goes, I got sunburnt on the only day of sunshine we had throughout the whole 2-weeks of our holiday!
It’s a long time since 1976, and it may well be a long time before we have another summer like this one, but with average annual temperatures increasing, it is sensible to reflect on the impact that climate change is having on our lives. Last week the Committee on Climate Change warned that “climate change means more action is needed to address risk of UK heatwaves and water shortages”. But what sort of action is needed and how will it affect our demand for energy?
As much as we like to think we can be independent of Europe in this country, there is certainly value in looking at what our European neighbours do when it comes to keeping themselves cool, especially when you consider that many of them usually have much longer and hotter summers than we do. Not surprisingly they are rather good at it. Eurostat data suggests that across Europe the total annual cooling load in buildings is 192 TWh. Now this sounds like a big number, the equivalent of boiling 0.5 trillion full kettles of water, but it is a whole order of magnitude less than the energy required each year to heat all the buildings in Europe, around 3,500 TWh. What is more, in the countries with the highest demand for cooling (Spain and Italy) the annual demand for heat in buildings is still more than three times the demand for cooling (in Italy it is as much as seven times greater!).
What can we learn from this? Undoubtedly, there is significant potential for ensuring that our building stock is fit for purpose. Centuries of experience mean that construction methods in Mediterranean countries are very good at ensuring that buildings remain cool in the summer without the need for air conditioning. We can learn from this, as long as we recognise that we also need to be designing our buildings to stay warm in the winter!
Some analysts suggest that in the future cooling demands across Europe could increase as much as six-fold if all indoor building space were cooled to a level that created an ‘ideal climate’. Given that this cooling demand is currently exclusively met by electricity, this could create a significant increase in electricity demand. Fortunately, with the other imperatives for creating an overall reduction in energy demand, further improvements in building design and the use of renewable energy sources for direct cooling, it is likely that these increases will not be as significant as the highest predictions suggest.
There is an on-going debate in Europe around these issues in which the energy needed for cooling buildings is considered alongside the energy required to heat them. This debate is characterised by a number of key issues:
- How far is it possible to go in improving the thermal performance of the building stock, taking a ‘fabric first’ approach, before the changes become prohibitively expensive?
- What is the potential for meeting residual demand for heating and cooling from the direct use of renewable energy sources (i.e. without first converting the renewable energy into electricity)?
- When is it appropriate to use heat pumps as a more efficient way of utilizing low-carbon electricity to provide heating and cooling services?
- Where can renewables and electricity be successfully integrated with other sources of heat to deliver district heating and cooling schemes?
- Who should be responsible for delivering the changes, what are their drivers, and what business models are available to them?
One issue that unites all those involved in the sector is the desire to see a greater focus on heating and cooling from policymakers and those directing innovation funding. Whilst it is broadly recognized that technical solutions are available to these issues, the key challenge remains one of establishing innovative approaches to integrating them into a more sustainable overall energy system, and, ultimately, achieving widespread uptake and commercial deployment of these solutions.
These demands have been recognized by the EC, as evidenced by the publication of their 2016 ‘Heating and cooling strategy’, which calls for action in four key areas:
- stopping energy leakage from buildings;
- maximizing the efficiency and sustainability of heating and cooling systems;
- supporting efficiency in industry; and
- reaping the benefits of integrating heating and cooling into the electricity system.
However, the main driver for change in the heating and cooling sector remains the need to reduce greenhouse gas emissions, whilst maintaining security of supply at an affordable price.
The use of renewable sources of energy is key to these aims, and there is a strongly held view in parts of Europe that electricity should only be used for heating and cooling where other renewable energy alternatives (e.g. biomass, solar, and geothermal energy) are not available for direct application. Primarily, the accessibility of such alternatives will be affected by the availability of resources and applicability of specific energy conversion technologies. However, other issues will also impact decisions around which are the most appropriate ‘low-carbon energy vectors’. These will include issues such as local energy markets, incumbent supply and distribution infrastructure, and historical, cultural, and societal imperatives.
This is a complex picture, but that just emphasises the need to keep innovating. We should continue to work at constructing larger demonstration projects, seeking to engage end users in desiring the benefits of new low carbon solutions, and finding ways to manage the commercial risks that they naturally bring with them.
This challenge calls to mind a Robert Frost poem:
‘…I shall be telling this with a sigh Somewhere ages and ages hence: Two roads diverged in a wood, and I— I took the one less travelled by, And that has made all the difference.’
…from ‘The Road Not Taken’