Heat Waves: Energy Efficiency and Nature-Based Solutions (Podcast)

[00:00:00.000] – Aristeidis Tsakiris

Welcome to the podcast series, Scaling Up Energy Efficiency.

[00:00:08.870] – Aristeidis Tsakiris

I’m excited to share that this is episode 12, where we will be discussing “Heat Waves: Energy Efficiency and Nature-Based Solutions”. Our podcast today is coming to you from the capital of Denmark, Copenhagen, which has been mandatory since 2010 for a large building with a surface area calculated according to a series of criteria to have a green roof. As of today, there are more than 200,000 square meters of green roofs. My name is Aristeidis, and I’m an advisor at the Copenhagen Center on Energy Efficiency, which is a part of the UNEP Copenhagen Climate Center. Now, let me introduce your host for today’s podcast, Clara Camarasa. She’s a Senior Advisor on Energy Efficiency, and we’ll be moderating our discussion.

[00:00:59.720] – Clara Camarasa

Hello, everyone, and welcome to today’s podcast brought to you by UNEP CCC and the Copenhagen Center on Energy Efficiency. I’m your host, Clara Camarasa. I’m a Senior Advisor at UNEP CCC, and I’m thrilled to have you with us for this episode. This podcast is part of our ongoing series focused on addressing critical issues in climate change and energy efficiency. In today’s episode, we will be focusing and discussing a pressing issue that’s only growing in urgency: Heat Waves. In fact, the UN Secretary General, Antonio Guterres, recently made a special call to action on this topic, emphasizing the urgent need for stronger global measures to tackle the devastating impacts of heat waves. As their frequency and intensity increased globally due to climate change, it’s more important than ever to understand how we can respond effectively. In today’s episode, we’ll explore the role of energy efficiency and nature-based solutions, or NBS, in mitigating their impact. And joining me today are three incredible experts, Dr. Rasmus Anker-Pedersen, Head of Unit at the National Center for Climate Research at the Danish Meteorological Institute, Dr. Nick Halfworth, Policy Advisor and Energy Analyst at the International Energy Agency, IEA, with extensive experience in cooling as well. And last but not least, Simrat Kaur, Energy Efficiency Analyst and India Coordinator at the International Energy Agency, bringing the case of India, which is a compelling case for addressing heatwaves due to its extreme climate variations, rapidly urbanization population, and the severe impacts of heatwaves on its energy system, infrastructure, as well as public health. So I’m excited to dive into this very important conversation with you all. Let’s start with the problem. Let’s begin by examining the link between climate change and heat waves. The reality is, as we all know, that as as our climate warms, heat waves are becoming more frequent, longer, and intense. These extreme weather events are putting enormous pressure on societies, economies, and ecosystems. Rasmus, let me start with you. Can you explain what the primary contributing factors are to the increasing frequency and intensity, of course, of heat waves?

[00:03:24.600] – Rasmus Anker Pedersen

Thank you. When we talk about climate change in general, there’s really one dominant factor behind it, and it is our global emission of greenhouse gasses. That is what has been driving the approximately one degree of warming we have seen until today. It is what we expect will continue to warm our globe with the current climate policies around the world to about a total of a three degrees warming at the end of this century. Now, that, of course, is all about averages across the globe and across the year. That’s often what you hear climate scientists talking about, such as myself. But what we’ll actually experience as the climate is changing is not so much the average, it’s actually the extremes. Of course, we assess the state of the climate in long-term perspectives, averages over 30 years. But when that average starts to move in a warmer direction, so do the extremes. That means we will more frequently we see temperatures that used to be rare, and the warmest days and the highest temperatures we experience will be warmer than we have been used to. That increases the chance of setting new records, as we have also seen in many, many locations across the globe in the recent years. Now, on top of that is, of course, the fact that our globe is not uniform, and some of these things are amplified in different parts of the globe and also affected by how we shape our societies. One clear example is our cities where they are often largely built off concrete and rock that can absorb and keep a lot of heat, which is further amplifying this warming that is ongoing. We talk about urban heat islands as something that is making these extreme temperatures even higher than in the surrounding areas. Where we live and on the concrete  days where we experience these high temperatures, that’s where we notice that things have started to change already.

[00:05:38.020] – Clara Camarasa

Thank you, Rasmus, for this thorough and very accessible, actually, explanation on factors contributing to heat waves. Yes, it’s clear that these heat waves don’t just impact weather patterns. They have profound effects on energy systems as well. Around the world, regions are facing threats to energy security, increasing strain on power grids, and even blockouts due to these extreme temperatures. Nick, given the IEA’s analysis and insights, what specific impacts can we anticipate in the energy sector as these heatwaves become more frequent and intense, and how our energy systems around the globe adapt adapting to this growing challenge.

[00:06:19.290] – Nicholas Howarth

Here at the IEA, we follow the energy data very closely. In 2024, this year, global temperatures set new records around around the world and looking across all regions, 50 countries hit record peak power demand during heat waves in virtually every energy-consuming region, from Japan and Korea and China, in Asia, through to North America, South America, across the Mediterranean, as well as in Africa, and down in Australia. This came as global electricity demand is also rising to record levels this year, up 4% expected. Now, this is the highest growth rate the world has seen since 2007. The biggest drivers are China and India, where cooling is a prime driver of overall demand. Those are some of the initial factors of what’s driving the relationship between heat waves and power systems around the world.

[00:07:28.420] – Clara Camarasa

Thank you so much, Nick, for this overview. And that’s actually a good segue for Simrat. Simrat, from your perspective and experience in India, what are some of the most severe examples of heat waves you’ve encountered? And how do these events impact urban areas in terms of access to energy, grid security, blackouts, et cetera?

[00:07:50.690] – Simrat Kaur

Thanks, Clara. So to talk about India’s story, India is actually one of the countries that is warming up faster than most of the world. It largely has a subtropical climate. And what we start to witness in the past couple of years is that many parts of the country, especially the Northern, Western, and Central India, has started to experience heat waves which are getting more intense, more frequent, and they tend to last much longer. In fact, this year, in the month of May, temperatures in many parts of the country crossed 50 degrees celsius, which is both unprecedented and alarming. I think the countries also started to witness this phenomena of missing the spring season altogether. So earlier, we used to have winter months up to January. And then the months of February and March used to be quite pleasant with summer’s beginning in April. But now what we started to witness is that we right away jump into the summer season in the month of February. In fact, In 2023, the month of Feb was the hottest ever recorded in 123 years. And if climate scientists tells us that due to climate change, These extreme heat events are going to become 30 times more likely in countries such as India. Now, the thing is that the repercussions of this heat stress are very disproportionate. If I’m to talk about occupational vulnerabilities, more than 50% of the labour force in India is working outdoors. So they’re employed in sectors such as agriculture, mining, construction, etc, leaving them with few opportunities to stay indoors and with lower access to cooling. In fact, there are estimates that the hours lost due to lower labor productivity due to heat could risk up to, say, 5% of India’s GDP in the coming years, which is in no way a small number. Talking a little bit more about access, currently, it’s estimated that one in 10 households in India has an access to an air conditioner. So most of the country actually relies on ceiling fans and evaporative air coolers to meet the cooling needs. And even with the current ownership level, we see that air conditioning loads contribute significantly to the peak power demand in summer months. In cities, such as Delhi and Mumbai, the contribution of the air conditioning load is as high as 40 to 60%. And in the coming years, we’ll definitely see a dramatic increase in the ownership of air conditioners. So for India, cooling is emerging as a developmental need. It’s important for the economy. It’s important for human health, for human health, wellness, and productivity. And the challenge for India going forward is to make a cooling accessible to all in a sustainable manner.

[00:11:03.930] – Clara Camarasa

Thank you so much, Simrat, for sharing such a crucial case and perspective. The facts and events are truly alarming, as you pointed out, and I fear that similar situations are unfortunately unfolding in many other parts of the world, as Rasmus also pointed out. Now that we’ve covered the scope of the problem, let’s shift our focus to the solution, to solutions. Energy efficiency and nature-based solutions have as critical tools in our fight against the negative impacts of heat waves. From reducing energy demand to enhancing resilience in cities, these are strategies that offer practical ways to mitigate the effects of extreme heat. Nick, from your perspective as a policy advisor and an energy efficiency policy analyst at the International Energy Agency, could you please explain how energy efficiency contributes to reducing strain on energy grids during the heat waves, and what are some of the most effective energy-efficient solutions currently available.

[00:12:04.120] – Nicholas Howarth

Okay, thanks. Well, when we talk about strain on energy grids during heat waves, what we’re talking about is how the need to keep cool boosts electricity demand through the use of air conditioning, putting stress on grids by forcing operators to bring older, more polluting plants into operation, or even threatening disruptions and outages. We’ve seen many countries experiencing blackouts and phased downs in the electricity supply in some places such as Mexico, Argentina, and particularly Pakistan this year. What energy efficiency can do is that a typical air conditioner on the market, which is highly efficient, can use around half as much energy as a typical air conditioner with poor efficiency. Now, this means a high efficiency air conditioner can cut the electricity needed for cooling in half. Now, this is great for the system operator, but it’s also very good for consumers because it means that overall bills to operate air conditioners will be lower by about half. Now, the extra good news is that our surveys of air conditioners sold on the market around the world suggest that these very efficient air conditioners that can provide around the same cooling with half as much energy actually even cost around the same to buy. So this is very good news. Other technologies that are very key to reducing grid stress can be things like smart digital or programmable thermostats that can adapt when people are not using buildings or used in the event of a crisis by utilities. Also, integration of solar PV with cooling systems to take pressure off peaks during the day when the sun is most powerful, and also, evaporative cooling for dry climates, which doesn’t need to use highly polluting F-gasses and coolant. So in a nutshell, those are some of the main things that efficiency can contribute to reducing grid stress from heat waves.

[00:14:39.440] – Clara Camarasa

Brilliant. Thank you, Nick, for sharing this overview. Great to hear about these good news such as that higher efficiency air conditioners do not necessarily have to come with higher upfront costs, for instance. Here at UNEP CCC, we also, of course, promote energy efficiency as a key strategy to reduce the impacts of heat waves. One of our flagship initiatives is the Global Partnership for Urban Cooling, GPUC, led by the Copenhagen Center on Energy Efficiency, which focuses on transforming how cities are approaching cooling. This is a project that has been designed to scale up the sustainable cooling solutions by integrating energy-efficient technologies and cooling strategies into the urban planning processes. And through this project, what we intend to do is to work with cities around the world to reduce cooling demand, promote clean cooling technologies, and improve the overall efficiency of urban cooling systems, thereby ensuring that cities are better prepared for future heatwaves. Another initiative here at UNEP is the District Energy and Cities Initiative, which is a central part of the UNEP work on promoting energy-efficient district cooling systems, which is a powerful solution for urban areas to significantly cut their energy use by optimizing cooling services across entire districts or even wider areas. And this initiative has already have success in several cities around the world, including China, India, and Chile, which serve as a model for others to follow. And talking about India, Simrat, from your experience, could you also highlight some energy-efficient solutions that have been successfully implemented in India?

[00:16:28.030] – Simrat Kaur

Sure, Clara. So when we talk about energy-efficiency solutions, I’m reminded of this study that was recently published, which looked at the indoor heat exposure in low-income households in several South Asian cities, including Delhi and Mumbai. And what this study found out was that the indoor temperature in these residential dwellings was actually higher than the outdoor temperature, which tells us that the building materials that are used in the construction of our walls or roof and the provisions for internal and external shading or for natural ventilation that a building allows determines how much cooling energy demand would be needed in that building. So that highlights the importance of better building design in enhancing building energy performance. And then, of course, like Nick mentioned, ensuring that the technologies that are being used to provide cooling, so whether it’s air conditioners, ceiling fans, or evaporative coolers, they are energy-efficient, can also help to solve the problem. In case of India, there are a couple of policies that have been helpful. The first thing is that India actually launched a cooling action plan in 2019, and India was one of the first countries to do so, which provides a 20-year outlook on how the cooling demand in India is going to evolve and what strategies, including both active and passive cooling strategies, would be important in managing this rising demand. In addition to that, India also has an energy conservation building code for both commercial and residential buildings, which is being adopted by several states. And it also has a very robust standards and labelling program in place for cooling appliances such as air conditioners as well as seating fans.

[00:18:22.860] – Clara Camarasa

Thank you so much, Simrat, for sharing the examples of successful energy efficiency projects in India. We have now shared some examples on energy efficiency measures, but of course, as you hinted at, there are other solutions such as nature-based solutions or NBS. At UNEP, we’re advancing nature-based solutions to complement our energy efficiency efforts by incorporating green spaces, urban forests, natural water bodies, or other natural bodies into our natural urban design, which creates a cooler environment through natural shading and other aspects, while also enhancing the local biodiversity, improving air quality, and fostering healthier, more livable cities, ultimately. Now, Simrat, talking about these solutions, would you tell us about some of the most effective nature-based solutions that are being used at the moment in India and what benefits they can bring?

[00:19:20.460] – Simrat Kaur

Right. So one of the most impactful examples I can think of is cool roofs, which are designed to reflect solar radiation and prevent the absorption of heat on to a building’s roof. And in India, it started with a couple of pilot demonstrations in various cities. And there’s evidence that compared with conventional roofs, cool roofs actually lower indoor air temperatures by 2-4 degrees celsius. So building on this case studies, several states, such as Telangana, have introduced a cool roof policy and have mandated that all government and commercial buildings in the state to have cool roofs.

[00:20:01.400] – Clara Camarasa

Brilliant case. So as we can see, both energy efficiency and nature-based solutions, in the case, you showcase offering incredible synergies, and together they can help create these resilient cities that are better equipped, ultimately, to handle the challenges posed by the revising temperatures. And this being said, these are not the only solutions available to sustainably mitigate and adapt to heat waves. Other approaches include advanced urban planning strategies such as smart city designs and optimising air flows and reducing heat islands, for instance, but also individual actions like energy-conscious behaviours that Nick pointed at and the adoption of, for instance, efficient home appliances, all of which altogether play an important role in creating a more resilient response to heat waves. Now, let’s discuss the policy side of things. Governments have a huge role to play in fostering sustainable cooling solutions, and energy efficiency and nature-based solutions are at the core of this. Nick, what policy instruments are needed to encourage the adoption of energy efficiency measures, particularly in areas that are more vulnerable to heat waves?

[00:21:17.190] – Nicholas Howarth

Thanks, Clara. And that’s right. And governments have a huge role to play in this. And here at the IEA, we’ve looked carefully at what works best around the world. And we suggest that a policy package approach of efficiency regulations, information support, and financial incentives across building, design, and construction and various cooling technologies is the best way to go. If we look at regulations first, in a nutshell, it involves putting building codes in place and ensure that they have robust dust requirements when it comes to things like insulation, windows and air sealing. The ASHRAE standards are a great place to start. Shading is also very important in particularly hot conditions, as is roof reflectivity, which Simrat mentioned with the cool roofs, as well as allowing the option for natural ventilation without mechanical cooling systems. Another really critical regulation is to put in place or strengthen minimum energy performance standards for AC systems. On the information front, energy labelling for buildings and air conditioning is really key at informing consumers, as well as programs to support behaviour through change, for example, through better thermostat controls and smarter digital systems that can help consumers adapt their use to conditions and system needs. But when we look at probably the fastest way to scale up action on efficient cooling, it’s in financial incentives. Now, these can include rebates that encourage people to exchange old, efficient air conditioners for high-efficiency ones, or low-interest rate green loans for efficient home renovations and constructions. That’s just a few of the main very quick examples.

[00:23:33.760] – Clara Camarasa

Thank you so much, Nick, for sharing this very comprehensive overview as well as the IEA perspective. I can also share that UNEP, through initiatives like the Cool Coalition, has been a key driver behind the cooling pledge, for instance, which calls for a significant reduction in the cooling-related emissions worldwide. As one of the main advocates of this global commitment, we have been playing a role or crucial role in helping countries as well in achieving these ambitious targets. Additionally, a strong global push towards doubling the rate of energy efficiency improvements by 2030 was reaffirmed, as we know, at COP 28. And with COP 29 and other key global platforms on the horizon, there’s a growing momentum for these energy efficiency and cooling solutions to be embedded into national policies. Now, looking at the way forward, Rasmus, given the current climate trends, what can we expect in terms of the future frequency and intensity, of course, of heatwaves? What key messages would you like to leave our audience with?

[00:24:45.400] – Rasmus Anker Pedersen

As mentioned in the beginning, we are looking into a future where as long as the emissions of greenhouse gasses continue as climate policies indicate they will, we are looking at a continued warming and therefore a continued increase in extreme heat. At the end of the century, we expect about three degrees of global average warming. But that said, if we look at the warmest days that we experience, for instance, the hottest day that we’ll see on average in 10 years, that looks to warm more than 20% more than the average temperature will. Said in another way, we will five or six times more frequently cross that limit, which is currently only happening every 10 years. In to a local perspective from Denmark, climate change brings other challenges than extreme temperatures. Mostly, we’ll be looking into more extreme precipitation and a rising sea level. But even in a cold country, we’ll see the effect of these increasing temperatures. If we look at heat waves, which is in Denmark defined as three or more consecutive days over 28 degrees celsius, we are looking at approximately a 50% increase in the frequency of those. It will still be a relatively rare phenomenon in Denmark that we reach that, but nonetheless, a big increase. That means we have to take that into consideration when we plan the adaptation also here in Denmark.

[00:26:23.160] – Clara Camarasa

Wow, very clear global, but also national in terms of the Danish overview and also the outlook. Thank you so much, Rasmus. And as we look to the future, it’s clear that we’ll need a comprehensive approach to effectively tackle these heat waves. The challenge is multifaceted and so must be our response. Nick, what are some of the key policy developments and initiatives in energy efficiency and sustainable cooling that you reckon will shape the response to heat waves in the upcoming years? And what should we expect to see at major upcoming events like COP, for instance?

[00:27:00.340] – Nicholas Howarth

So first, I’d just like to highlight just how far we’ve come. It was only just under 10 years ago that the IEA and their Future of Cooling report identified cooling as one of the most important critical blind spots in energy policy. And since then, we’ve really come a long way to today, where it’s very high on the international agenda and cooling systems are seen as part of the critical infrastructure of national importance for health, food security, energy security, as well as economic stability. So we’ve really come a long way to address this blind spot. And I can think of no other indicator of just how far we’ve come. Was last year at COP 28, we had a historic agreement to double energy efficiency efficiency progress, the rate every year. But as an important part of that was the global cooling pledge, which had within it, and UNEP was incredibly important in securing this commitment, a commitment to collectively increase the global average efficiency rating of new air conditioning equipment sold by 50% by at the latest 2030 at the global level from a 2022 baseline. It’s really fantastic to see these quantitative targets being agreed by the community of nations and cooling right at the front of the agenda. That will be a really key part of this overall agreement to double the annual global rate of improvement in energy efficiency. As part of this, at the national level, we’re seeing many countries who are particularly vulnerable to heat waves, now developing national cooling action plans. And just earlier this month, in August, Indonesia launched their plan, bringing together policies on not just efficiency, but also low greenhouse gas refrigerants, as well as cold chains for refrigerated transport and storage. Countries are introducing requirements for digital demand response into their minimum energy performance standards for cooling systems, such Japan this year. This will really help manage extreme events like heat waves, but also other emergencies that impact on energy security. I’d also like to just highlight the ongoing work of the Super Efficient Appliance Deployment Initiative, SEAD, being developed through the Energy Efficiency Hub, working with countries around the world to harmonize and strengthen minimum energy performance standards for cooling and really draw on the best practice of what works and how best to go about it to make that process as easy and seamless as possible. There’s a lot to look forward to, and we’ve really moved from the point of blind spot to now we’ve got some high-level commitment, and now it’s a matter of implementation and moving forward with the plan to bring about the solution to these goals that have been articulated.

[00:30:28.330] – Clara Camarasa

Thank you, Nick. As you described, we’re now entering a crucial phase of implementation. As we look ahead, it’s clear that addressing heat waste requires an integrated approach that combines technology, policy, and also nature. The UNEP were deeply committed to advancing energy efficiency and nature-based solutions as a central pillar in the fight against climate change and the impacts of heat waves, as we believe that together, energy efficiency and nature-based solutions offer a powerful complementary as well, response to the growing threats of heat waves. And with this said, I thank you. I thank our speakers, Rasmus, Nick, and Simrat, for your invaluable insights today. This conversation has highlighted not only the scale of the challenge, but also the powerful solutions at our disposal. To our listeners, thank you for joining us today. Heat waves might be a growing threat, but with the right strategies, we can build a more resilient and sustainable community. East and livable cities for all. And please stay tuned for more episodes in our podcast series as we continue to explore innovative climate solution. All the best and goodbye for now.

[00:31:43.380] – Aristeidis Tsakiris

Thank you for tuning in to the podcast, “Heat Waves: Energy Efficiency and Nature-Based Solutions”, featuring Nicholas, Simrat, Rasmus, and Clara. If you enjoy the show, please feel free to share it on your social media platforms. For additional information on today’s topic, please visit the Copenhagen Center Energy Efficiency web page. Stay connected and subscribe to receive notifications of our upcoming podcasts. We look forward to seeing you at our next episode, and always remember that energy efficiency is a journey, not a destination. Cheers.