Chapter 2
Energy and Electricity
EnWave Corporation is a private company that owns a large steam-heating district energy system in downtown Toronto and an equally large district cooling system. It is a successor to the Toronto District Heating Corporation (TDHC), the city-owned utility that supplied highly efficient district heat to public buildings in Toronto starting in 1980. At that time the steam-heating subsidiary of Toronto Hydro (owned by the city) merged with the Toronto Hospitals Steam Corporation to become TDHC. It later built the first large-scale municipal district cooling project in the world, which opened on August 17, 2004. The idea for the district cooling came from the brilliant engineer Robert Tamblyn, who reportedly got the idea for district cooling when he was working at the T. Eaton department store in the 1940s. At the time, the company used fans to blow air across the cold-water pipes to cool the women’s nightwear section. Mr. Tamblyn’s insight and brilliant engineering eventually led to the use of cold lake water to cool most buildings in downtown Toronto using less than a tenth of the energy required by traditional cooling systems. On October 4, 2012, Mr. Tamblyn died at age ninety-one. In a very odd coincidence, on the same day, legal approval was given for EnWave to be privatized by the City of Toronto and sold to Brookfield Asset Management.
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On a cold winter’s day in Toronto, Canada, the air will be remarkably clear, and the sky brilliant blue. The sun will sparkle off Lake Ontario, and if there has been a recent snowfall, the snow will glisten. There might be a little ice on Lake Ontario pushed to the shore by the action of the waves. The peaks and troughs are highlighted by the low angle of the sun.
From Exhibition Place, adjacent to the shore of Lake Ontario, on such a day you might be able to see the mist of Niagara Falls hanging in the sky, more than forty miles away across the lake. In the foreground, you will see a 299-foot-tall cream-colored wind turbine, standing high into the sky, and you might possibly hear a slight hum. Installed in 2002 by the Toronto Renewable Energy Collective, the turbine was the first within the urban boundaries of a major North American city. It’s a highly visible demonstration of Toronto’s commitment to sustainable innovation.
Each year, Exhibition Place attracts more than 5.5 million visitors to its trade and consumer shows, the popular and highly successful local soccer team Toronto FC, and the Canadian National Exhibition. All the visitors will see the wind turbine, but what they do not see is equally as impressive. On the flat rooftops of some of the industrial buildings that are lined up on the north side of the exhibition grounds are two giant solar arrays. Hundreds and hundreds of solar panels silently, quietly, and efficiently generating electricity. At installation, both of them could claim to be the largest urban solar array in Canada. As well, there is a highly efficient trigenerator on site – meaning that Toronto’s historic exhibition grounds generate as much electricity on site as they consume, despite being busy with multitudes of energy-intensive events virtually every day of the week, year round.
The WindShare ExPlace Turbine. Owned by the Toronto Renewable Energy Co-Operative (Windshare), the project was built to demonstrate the viability of a wind turbine in an urban setting. It generates from 600 to 625 kilowatts or about enough power for a neighborhood. Source: NicolasMcComber/iStockphoto.com.
Clean Electricity Is Critical to Climate Action
Exhibition Place is a showcase of what creative city leadership can do to address the critical issue of greenhouse gas emissions from the generation of electricity. It is well established that how we generate electricity has significant consequences for climate change. Coal, for example, when used as the fuel for electric power plants generates substantial carbon dioxide (the most significant greenhouse gas), as well as nitrogen oxide, mercury, dioxides, and other serious air pollutants.
The figures used in this book for estimates of greenhouse gas emissions by cities will typically count emissions from electricity generation, including those from a plant that supplies a city, even if it is outside that city. At the same time, cities’ regulatory authority over or ownership of electric utilities varies significantly. In some jurisdictions such as Texas and California, cities will own the utility that generates electricity; in others such as Ontario, they will own the distribution utility; and in still others they will have no direct authority but will have considerable influence. Whatever the legal role, cities have recognized how critical it is to move rapidly to clean sources of electricity and are taking serious measures to do exactly that. The role of mayors in advocating for a broader energy transition – closing coal- and gas-fired power plants, for example – is important, as are the creative actions of those mayors in finding other ways to unlock and expedite a transition to clean energy.
This chapter will explore examples of effective leadership from cities that have significantly decarbonized their electricity – starting with those that do own their utilities.
Municipally Owned Utilities: The Emergence of Distributed Energy
Historically, electricity has been usually generated by large power plants, and the electricity distributed by power lines over long distances to those who use it, with the possible exception of certain power plants designed to support particular industrial operations. This traditional model of generating and transmitting electricity is known as a “grid,” but conceptually it is being challenged by modern technologies. It is now possible to think of electric power as something being potentially generated in small amounts at a household level, with any excess being sold back into the grid for consumption by others. (Germany is the best-known example of this new approach, which is called distributed energy.) Solar power – fueled by sunlight – is an example of a renewable source of energy that can be successful in many places today, at a very low cost. Unlike fossil fuels, solar is clean – and does not run out. Essentially, solar photovoltaics (known as PVs) turn sunshine directly into electricity through solar cells made of silicon wafers that are assembled into the solar panels we see, which generate direct current (like batteries). If used at a household level, the electricity generated is fed into the electrical panel through an inverter that changes the electricity from direct current to alternating for use in the house or in appliances.
Austin Energy: Bold Leadership from the City that Proudly “Keeps It Weird”
Austin, Texas, is hot in the summer. Very hot. Over the past twenty years, it has been having on average more than thirty days of temperatures above 38°C (100°F) per year, and that average is rising, likely due to the impact of climate change. That weather means more demand for air conditioning, which uses more electricity, which generates greenhouse gases, which cause global warming, which causes extreme heat days in Austin. It is a vicious cycle, one that Austin is working hard to change. In 2007 Austin City Council resolved to “make Austin the leading city in the nation in the effort to reduce the negative impacts of global warming,” setting a goal of reducing greenhouse gas emissions to 20 per cent below 2005 levels by 2020 and being net zero by 2050. (Net zero means if there are any greenhouse gas emissions greater than zero, they will be captured or offset; for example, by sequestering in concrete or by planting trees, both of which remove carbon from the atmosphere.)
The electric utility in Austin (Austin Energy) is municipally owned, and the city has worked with Austin Energy to make significant progress on its climate goals. (There are two or three other smaller utilities in the county, including that of the University of Texas. They have cooperated with the city as well.) In addition to environmental constraints, Austin has had a significant period of population growth and regulatory constraints over the price of electricity. Electricity prices cannot rise by more than an average of 2 per cent per year, and overall rates must remain below the fiftieth percentile for the state of Texas.
The approach of the city and its utility to these challenges has been highly effective. It involves a combination of reducing demand through conservation, investment in energy-storage solutions, peak-demand management, and investment in local solar projects. In 1982, Austin Energy began to build what it calls a “Conservation Energy Plant.” Rather than build a new power plant to supply growing demand for electricity, Austin developed conservation programs to offset that growing demand and eliminate the need to build new capacity. The program focused on the energy efficiency of buildings and electrical equipment and it worked – the utility avoided building a new plant and saved significant costs while doing so.
That approach was so successful that Austin is creating its second Conservation Energy Plant. Electricity rates are used to help incentivize reduced use: rates increase step-wise with consumption. Peak-demand management involves a voluntary program for homes and businesses in which Austin Energy remotely controls the thermostats for limited times on peak-demand days. A district chilling system has also been developed whereby ice is made at night and the cool water is used to cool the buildings in the hot part of the day. Finally, Austin has invested heavily in local and utility-scale solar projects. In the city, you can subscribe for 100 per cent renewable energy, rebates are offered for solar installation, and higher rates are offered for locally generated solar.
Because a significant portion of Austin’s greenhouse gas emissions comes from electricity use in the city, renewable sources of energy are a priority. The current energy supply is a mix of wind, natural gas, coal, nuclear, solar, and biomass. By 2022, the city plans to end the use of coal power, but a full switch away from fossil fuels requires an energy supply that is flexible, reliable, and predictable, and it also requires energy storage. These technologies are in development to support the expansion of renewable sources that are intermittent. Austin Energy is considering many possible approaches, from large battery storage to thermal storage, to compressed-air energy storage.
Austin Energy offers rebates to help reduce the cost of installing residential solar systems and pays residents for the electricity they generate. It says the most optimally positioned solar PV system faces due south and is tilted to a thirty-degree angle. If a south-facing roof is not available, west facing is generally the next best, and east-facing solar panels also work. Source: RoschetzkyIstockPhoto/iStockphoto.com.
“As your mayor, I’m proud to have joined almost 400 other US mayors to adopt, honor and uphold the Paris Climate Agreement. I reiterated our commitment last October at the Paris Climate Conference and again in December when I signed the Chicago Climate Charter at the North American Climate Summit.
Last year this Council, thanks to the leadership of CM Pool, upped our renewable energy goals from 55 per cent by 2025 – to 65 per cent by 2027 (and asked for a plan to get us up to 75 per cent). This is one of the most ambitious clean energy goals in the country. And we’re well on our way toward meeting that goal. We’re beginning the process to close our only coal plant and increase our use of renewable clean power at Austin Energy.
Last year we bought more solar and wind to push us over 50 per cent renewables by 2020. The economics of such energy have gotten so competitive, that the last renewable energy contract signed by Austin Energy will serve to reduce the rate-payer cost.”
– Mayor Steve Adler (Austin), State of the City address, 2018
In pursuit of these goals, the city has worked with Austin Energy to create an ambitious residential rooftop solar program. The program provides subsidies and incentives to residential homeowners to install rooftop solar, and the utility commits to buying excess electricity from the homes. Priced in a way that encourages homeowners to install the solar panels, the utility is still saving money over the cost of building a new power plant. Combined with industrial-scale solar installations and energy from wind, Austin Energy is confident of meeting its current target of 65 per cent generation by renewables by 2025.
The City of Austin has led the way in moving to renewable energy in its own operations. By 2012, municipal buildings were powered with 100 per cent renewable energy, and Austin was the first large municipality in the United States to reach this goal.
This municipal leadership is important. Although Austin is a progressive, modern city, with a world-stature university, a massive annual music and arts festival (SXSW – South by Southwest), and a wonderful slogan – “Keep It Weird” – it is still in the heart of Texas, the world capital of the oil industry. It would be difficult indeed to ask residents to adopt significant new technologies to move away from oil and gas if the city government itself could not point to its own success.
The plan is Austin is working. By 2018, 38 per cent of all electricity citywide was sourced from renewables and included more than eight thousand rooftop solar installations. This success has allowed Austin to think about doing even more, and it is in the midst of developing a new action agenda to do more faster, starting by reviewing the feasibility of shortening its timelines and increasing its targets.
“In government, things don’t just happen by wishing ... later on, you find that people have now bought into the idea and understand the benefit of what we are achieving. Then it’s much easier – you have leadership at all levels bought into the new way of doing things.”
– Mayor Patricia de Lille (Cape Town), 2017
Municipal Utilities: Los Angeles
Los Angeles is another powerful example of leadership by a city that owns its electric utility – in this case the Los Angeles Department of Water and Power.
The LA climate plan – LA’s Green New Deal – aims to improve the lives of the residents of Los Angeles, particularly the most vulnerable citizens, while dramatically lowering greenhouse gas emissions. As a part of this strategy, the plan’s goal is to use 100 per cent renewable energy by 2045. In the near term, the target is 55 per cent renewables by 2025. The plan has a three-pronged approach: progressively increase local solar, add energy storage, and use demand-response programs. The LADWP has pledged to end all fossil fuel generation by 2029 (except for an already underway project to convert to natural gas a coal-fired power plant owned by the LADWP but located in Utah). LA’s sources of greenhouse gas emissions are set out in Figure 2.1.
Figure 2.1: LA’s Greenhouse Gas Emissions, 2013–2017
Emissions in the LA area are declining. With new action in the Green New Deal, they are set to decline much faster. Source: Based on data from City of Los Angeles, LA’s Green New Deal: Sustainable City Plan 2019, 2019.
LA has succeeded in shifting electricity to renewables from coal, as shown in Figure 2.2.
Figure 2.2: LA’s Electricity Mix Shifts, 2007–2017
Los Angeles has started relying more on renewable energy to reduce dependency on coal-based energy. Source: Based on data from California Energy Commission, published in the Los Angeles Times , “Los Angeles Is Finally Ditching Coal,” 16 July 2019.
Los Angeles has very significant grid-scale solar today. (Grid scale in this context means a large power plant. In the case of solar it would typically mean a giant solar array located outside a city, often in a desert or other place with near-continuous sunshine.) Since 2013, LA typically has had the most solar capacity of any US city. Today, the equivalent of more than half a million homes could be powered with the power output of Los Angeles’ wind and solar installations currently owned by the LADWP.
LA has also been making strides to enable significant solar installations within city boundaries by launching a feed-in-tariff (FiT) program in 2013. A feed-in-tariff is a way to pay people for electricity they generate, often but not exclusively at small scale (such as rooftop solar). It is an important step toward a program of distributed generation. When completed, LA’s program will have enabled 150 megawatts of large solar installations on rooftops and vacant land in the city, about equivalent to the energy produced by one-fourth of a new natural gas power plant – significant indeed.
As part of a longer-term strategy, incentives were available between 1999 and 2018 to subsidize the purchase of solar panels, with greater subsidies available to governments, nonprofits, and affordable housing. That program has now been terminated because the dramatic reduction in the price of solar PV has meant that the incentives are no longer economically necessary. They were extremely effective: over twenty years they helped to create 268 megawatts of power from 34,440 installations.
LA recognizes the importance of equity when it comes to solar power – that the cost of electricity (and the economic benefits from a feed-in-tariff) should be shared by all residents. Accordingly, through the Solar Rooftops Program homeowners are able to lease their roof for the installation of solar panels, and the Shared Solar Program allows residents of multifamily dwellings to subscribe to offset portions of their energy use with solar energy every month at fixed prices for terms of up to ten years. Both programs are designed to allow underrepresented groups (such as low-income residents and renters) to participate in the solar market and benefit from solar savings.
The Green Power Program also allows participants to source all or a portion of their electricity from green power for a small increase in cost. By 2021, LA hopes to add energy storage to its FiT program, require all new parking structures to have solar panels, and launch a program to allow residents of multifamily buildings to share the economic benefits of solar installations on their buildings.
LA has significant plans for energy storage that focus on the development of a renewables hub in facilities owned by the LA Department of Water and Power in Utah. The LADWP currently owns a large share of a big coal-fired power plant (the Intermountain Plant) in Utah, as well as the transmission lines that bring the power to LA. Renovations are underway to retrofit that coal plant with natural gas, dramatically lowering emissions. At that site, there also is significant potential for grid-scale solar and wind, which could use the same transmission lines and lessen reliance on the gas plant, with appropriate storage. Possibilities include compressed-air energy storage using a large onsite natural salt dome, renewable hydrogen, large-scale flow batteries, and solid oxide fuel cells. Storage can help ensure that intermittent sources of power – such as wind – become grid-scale reliably.
Los Angeles has focused on shifting demand by commercial, industrial, and institutional customers from peak times to off-peak times. Those that sign up for the program develop plans to reduce their demand by a minimum of 100 kilowatts. When notifications are given for a demand-response event, participants enact their plans. LADWP ensures that demand-response events are no more than four hours long and that no more than twelve demand-response events occur per year. As incentives, participating businesses receive monthly payments in the hottest part of the year for every kilowatt reduction of energy use promised and also compensation for the energy they do not use during each event.
In 2018, 447 megawatts of electricity were conserved in this program by its forty-three participants. It has proven so successful that it will be automated by 2021. It is popular as well, with participating businesses being paid nearly US$500,000 in 2018. A demand-management program for residential properties (similar to that in Austin) will be added soon, and Los Angeles is also reviewing the potential for electric vehicles and smart meters to help with demand management.
Creative City Leadership
The strategies undertaken by LA and Austin are made possible because of public ownership of the electricity grid and the utility that generates power. The creativity with which they have both approached issues such as expanding solar suggests ideas that can be utilized by other cities, even if they do not own the utility. For example, cities can and do support solar and other programs through a variety of schemes, including their own purchasing of electricity, and use ways to generate heat or cooling that significantly reduce reliance on electricity or fossil fuels. Three interesting and effective initiatives are explored below.
City governments are using a variety of these types of methods to dramatically lower greenhouse gas emissions from the generation of electricity, even where they do not control the electricity grid or own the plants that generate electricity. In Vancouver, Canada, for example, heat is taken from sewer pipes through a heat exchanger and used to heat and cool buildings – thereby ensuring that those buildings do not need to use natural gas or electricity for that purpose. The underlying technology has been commercialized and is spreading rapidly in numerous cities globally.
Toronto has an interesting system by which it uses cold lake water instead of air conditioning to cool buildings. In the summer, cold water from Lake Ontario is piped from the lake to a network of public and private buildings in downtown Toronto, where, through a heat exchanger, the air is cooled. Known as Deep Lake Water Cooling (because water at the bottom of the lake stays the same temperature – just above freezing – year round), the system is owned by the utility EnWave.
Although now a private company, EnWave was originally a steam-heating cooperative owned by the City of Toronto, the University of Toronto, and the major downtown teaching hospitals. Subsequently the city bought out the shares of its partners and, as sole owner of EnWave, developed the Deep Lake Water Cooling concept. The system currently serves about seventy downtown office towers and public buildings – most of Toronto’s downtown core – and is set for expansion. At inception, the system allowed office towers to end the utilization of electricity for air conditioning, which had a significant positive impact on greenhouse gas emissions. At that time, electricity for peak consumption – such as air conditioning on very hot days – was generated by a coal-fired power plant. Although in Toronto’s case the coal plant is now closed, the principle remains that cities adjacent to a large body of water can have a technologically feasible, affordable, and clean source of cooling that does not rely on fossil fuels or electricity (except for small amounts of electricity needed to run pumps, etc.).
Similar principles exist with district energy – where multiple buildings are heated from a central power plant. EnWave, in Toronto, was originally incorporated as the Toronto District Heating Corporation to supply district energy to its partners – an efficient, cost-effective system. Today, we realize that such systems have a significant benefit for our climate as well.
An excellent example is in Copenhagen.
District Energy in Copenhagen: Efficient, Cheap Low-Carbon Energy
Copenhagen has one of the most ambitious climate mitigation plans of any city in the world: it plans to be carbon neutral by 2025 and entirely fossil fuel free by 2050. With about 60 per cent of its greenhouse gases coming from buildings, addressing the emissions associated with the electricity and heat used in buildings is essential. Copenhagen has a significant advantage here, as virtually all buildings in Copenhagen are connected to a district heating system. The system goes back almost to the turn of the last century but became critically important as a consequence of national policies enacted during the 1970s’ oil crisis.
District energy is highly efficient and cost effective, and the policies that created it were farsighted. In the 1970s, Denmark ended its reliance on oil as a strategic choice – but moved to reliance on coal. Thus we have seen over the past twenty years a movement in Copenhagen to find other, cleaner sources of power to create electricity and power the district energy system.
In Copenhagen, power plants channel their waste heat into the district heating system. Electricity and heat production are therefore inextricably linked. Current fuel sources for these combined heat-and-power plants include coal, oil, natural gas, wind, biomass, geothermal, and waste. Wind energy is growing in Denmark, and Copenhagen aims to build one hundred new wind turbines by 2025. To build support for the turbines, the city has run awareness campaigns and offered tours of existing turbines, and it has also allowed citizens to invest in wind energy – a strategy that may well be key to public acceptance of the project, as Danes directly benefit financially from the clean energy generated by the turbines. (The Danes love co-ops. I was told a joke while in Copenhagen recently: “Two Danes get on the train to Copenhagen and by the time they arrive they have started three co-ops.” I don’t understand the joke, but it is illustrative of the concept.)
Recent strategies have focused on converting coal, oil, and natural gas plants to be capable of using biomass by the end of 2020. Biomass consists primarily of sustainably harvested wood pellets and straw, both of which are considered renewable and are carbon neutral. These power plants are essential complements to the wind and solar power plants as they can provide stable base loads and can change their power output rapidly to meet fluctuating demands. One controversial area in Copenhagen is that waste incineration is also a major source of both energy and heat. The city is making an effort to address this issue by diverting waste, when possible, to better uses. Efforts to recycle and divert plastic from waste have therefore increased, as has the diversion of organic material from waste. These organics (together with sewage waste) are being used to generate biogas for use as a general fuel and in vehicles, and the city is actively working on its longer-term goal of eliminating the use of waste incineration entirely.
Copenhagen’s district heat system is huge and complex. It includes over 1,500 kilometers of double pipes (incoming hot water/steam, outgoing cooled water/steam) and has separate operators for production, transmission, and distribution. Once in the building, heat exchangers are used to move the heat from the district system to the building’s water-based heat system. The system is far more efficient than using a furnace or boiler in every home, which reduces emissions and also saves money: it is estimated that it would cost twice as much to heat the buildings in Copenhagen with conventional systems based on oil or natural gas, and the centralized system also allows for better pollution controls. Two small district cooling systems have also been added to the system. These use seawater and waste steam to help cool buildings.
These programs are working: by 2015, total greenhouse gas emissions were 38 per cent below 2005 levels, despite a 16 per cent growth in population. And with such a comprehensive long-term plan, Copenhagen is on track to achieve far more.
In the long term, beyond 2025, Copenhagen plans to move away from biomass, replacing those plants with geothermal energy and heat pumps. A large-scale heat pump pilot project that collects heat from seawater and wastewater was connected to the district heating system in 2019, and by 2025, the city plans to launch a large geothermal energy plant for clean energy.
District heating isn’t an idea only for Denmark; it is a highly efficient and effective way to reduce the use of energy, even when powered by polluting sources – and, of course, is even more effective when a transition is made to clean energy sources as in Copenhagen. It is an example of large-scale success at an urban level of innovation. Today, cities are testing geothermal, solar thermal, and other technologies in addition to the sewer-heat recovery mentioned above. All of these initiatives have significant potential to reduce reliance on fossil fuels and electricity to heat and cool buildings, or to generate clean electricity, and all are feasible – today.
The Final Word
City governments have demonstrated that a large-scale switch to renewable sources of generation is possible now, ending reliance on fossil fuels – at a minimum, drastically reducing the use of coal, oil, and natural gas to generate electricity. They have also demonstrated that through creative actions such as district heating and cooling, and emerging technologies such as heating from wastewater, the use of electricity from power plants can be dramatically reduced.
This leadership shows that arguments made by some that we have to keep relying on dirty power simply are not true. We know how to both generate clean electricity at scale and create systems that heat and cool our cities in ways that don’t rely on fossil fuels at all. Through these methods our urban areas can see significant reductions in greenhouse gas emissions – according to McKinsey, up to 45 per cent reductions are possible using today’s technologies and systems, right now. And in places where mayors cannot directly make the needed changes, they can use the power of city government to influence that change – just as Mayor de Lille in Cape Town and as the City of Toronto did, through innovative use of wind, solar, and deep-lake cooling.