In the sustainable energy and buildings priority sector, the greatest potential for reducing CO2 emissions is from making changes to the sources that effectively cover the city's electricity consumption. With the help of newly constructed solar, hydro, and other zero emission power plants, Prague’s electricity supply can be secured without coal by 2030. This will reduce carbon emissions by approximately 2.5 million tonnes (22.5%) despite the expected growth in electricity consumption due to the development of electromobility and increased electrification of the heating and cooling sector.
The second most significant area of CO2 emission savings is the decarbonisation of the (district) heat production and supply sector. However, a prerequisite for the successful realisation of the CO2 savings potential is a significant change in the city’s role of in the energy sector. Cities that are successful in reducing their carbon footprint generally have ownership of all energy infrastructure and are able to effectively coordinate and link its development to benefit long-term goals, including those relating to climate.
The heat supply system (here referred to as "SZT") is a valuable energy infrastructure for the city of Prague. Its problem from the perspective of the city's climate policy is that 85% of the heat supplied through the district heating system originates from the high-carbon emission coal heating plant in Mělník, and the city has almost zero possibilities to change the heat source in favour of a lower carbon footprint. For this reason, the city wants to make a strategic decision in the near future on how to further develop the heating sector - whether to choose the option of owning a central supply system or to focus on developing significantly decentralised (local) sources.
The third major source of CO2 savings is from buildings - there are more than 130,000 buildings in the city, where for the vast majority it is still possible to identify and implement measures to reduce energy consumption, especially in relation to heat. The Climate Plan foresees a reduction in the sector's overall energy consumption (including industrial buildings) of almost 10%, which would correspond to a reduction in the carbon footprint of around 0.5 million tonnes per year. CO2 savings from the development of local electric power sources can increase this figure further by nearly 0.4 million tonnes.
What are our main goals in the field of sustainable energy and buildings?
The following priorities have recently taken shape and we consider them absolutely crucial. We see their successful resolution and implementation as our personal commitment. These are:
- New power plants using renewable sources (so-called RES)
- Advancement in the renewal of the current building stock to increase standards suitable for a 21st century metropolis
- New construction as an opportunity for a city of short distances and demonstration of the attainability of carbon neutrality
- Reducing the carbon footprint of heat production
- Environmental accounting and the carbon budget
List of proposed measures
In light of the information above, it is necessary to implement well-formulated measures which will play a key role in reducing the carbon footprint of the city in the areas of production, supply, and use of energy, especially in buildings within the city area:
- Introduce a system of energy management and gradually implement it in all sectors of energy use. With its aid, evaluate the effectiveness of implemented measures and research new possibilities. Monitor the fulfilment of the city’s climate pledge.
- Complex and unified drafting of investment projects across the different Prague City Hall departments which fulfil the requirements of modern renewals of the 21st century, including the introduction of more rigorous internal standards for economically advantageous renewals of properties in city ownership, as well as increasing their numbers/volume; support of these steps will result in an increase in the demand for skilled labour and the number of workers who will focus on putting together and evaluating investments.
- Lower the city’s carbon footprint related to the production and distribution of heat with the help of an active approach and aim to utilise the gained heat energy from renewable and secondary sources to its maximum potential. This will be supplemented with heat production using natural gas; however, this will only be used in the form of so-called high efficiency cogeneration together with the current electricity production which will allow to fully substitute the production of heat using coal with other methods by 2030.
- Establish the Prague Renewable Energy Community supplying energy from renewable sources; first for city buildings and later by expanding to city districts and city organisations in city ownership, and finally to inhabitants and institutions operating within the city. Through this new medium, the city intends to accelerate the construction of new production plants utilising renewable energy sources to cover the energy needs of the city.
- Establish a city revolving or climate fund supporting projects of energy savings and the utilisation of RES (ex. interest-free loans for city or residential buildings, sufficient funds for pre-project planning, etc.).
- Expand the Clean Energy for Prague programme with measures focused on adaptation, higher use of RES, progressive renewals in low or passive energy standards.
- Offer complex consultation services (partially financed from the revolving fund) for inhabitants and residents, providing information about suitable renovations of family and apartment homes (so-called One Stop Shop), including financial support for applying for national grants.
- Transfer of modern technologies and processes in sustainable energy into practice in public administration of the Prague City Hall , primarily through partnerships in prestigious international projects (HORIZON 2020, ELENA, etc.).
- Gradually modernise systems of electricity, heat, and gas distribution , aiming to introduce smart systems of monitoring (especially in the case of electric power) and reduce losses in the networks, that is, also reduce the carbon footprint of energy infrastructure.
This will inevitably lead to energy savings, which can make living in the city more convenient and enjoyable. The system of proposed measures is based on an appropriate blending of two inseparable approaches - mitigation and adaptation. While mitigation aims at areas where it is still possible to take meaningful actions to reduce the environmental impacts of human activities, adaptation works with an already changed status quo and tries to adapt or "rework" it as much as possible. The emphasis on sustainable energy, education, and efforts to involve the public as broadly as possible undoubtedly fall into the first category. In the case of modern renovations of buildings and inclusion of elements for self-sustained energy production or blue-green infrastructure, we are talking more about the latter.
With these factors in mind, we have defined the following four priorities which we consider absolutely crucial. We see their successful resolution and implementation as our personal commitment. These are:
- New power plants using renewable sources (so-called RES)
- Advancement in the renewal of the current building stock to increase standards suitable for a 21st century metropolis
- Reducing the carbon footprint of heat production
- Introducing a system of environmental accounting and a carbon budget
With what projects do we want to achieve the proposed goals?
The reason behind the hierarchy of measures for sustainable energy and buildings is based on a simple premise – a city cannot ask its residents to do something that it does not practise itself. Moreover, without sufficiently support, we can hardly hope to get the majority of the public on our side. That is why we want to start at the city level - Prague possesses a large enough building stock to indicate the path that similar projects should take through the medium of pilot projects. But it is not just about what Prague owns. The Prague City Hall has unique tools at its disposal which can help in motivating both citizens and the private sector.
The Prague Renewable Energy Community
Visions of creating a central place for energy distribution at the city level have already been put forward by previous governments. We are now standing at Prague's tipping point, separated from it only by a small step. Moreover, with added value for those who want to not only be passive recipients but also active producers of clean renewable energy.
The establishment of the Prague Renewable Energy Community represents a unique opportunity to connect the public and private sectors. In fact, it is a prime example of how a city can motivate companies operating within its territory, as well as residents themselves to get involved in a larger initiative while understanding exactly what benefits it will bring for them. The actual implementation of this project can be compared to the establishment of a very closely defined cooperative. In the first phase, it will focus its attention on buildings owned by the city. By cooperating with other sectors, which is already very much ongoing at the level of the city districts and city-owned organisations, we will then accelerate the pace at which the replacement of current external fossil fuel sources with purely urban ones based on the extraction of renewable resources. The ambition is that these options should eventually become available to the residential and business sectors.
The existence of such entities is explicitly foreseen and supported by European legislation currently in effect. On the whole, it works with the idea of a “renaissance” of photovoltaics, whose reputation is still tarnished in the Czech media space by various corruption cases. With the creation of the Prague Renewable Energy Community, we are trying to promote a boom of civic photovoltaics and show its potential for the quality of life in a metropolis like Prague. It will have benefits in terms of reducing CO2 emissions and household energy savings. Moreover, thousands of buildings in Prague have the capacity to install PV panels, so it would be a shame to let this potential go to waste.
Prague Renewable Energy Community
The existence and activities of the Prague Renewable Energy Community should be based on the relevant provisions of European regulations (specifically EU Directive 2018/2001). Its founder should be the City of Prague, with the aim of accelerating the installation of PV or other emission-free power sources, first implemented on the city’s property and then on properties of other owners.
The Community would provide the following services starting with its establishment:
- Developer and operator of newly constructed green power generation facilities on buildings and other properties of the city or other persons,
- supplier of other green electricity to the customers - members of the community,
- purchaser of surplus "green" electricity from embedded generation plants installed at sites owned by the city or other persons.
With the help of the community, the city will be able to overcome the economic and technical barriers that prevent the establishment of green electricity generation plants today and, in view of the powers and principles of operation defined by the legislation, will offer membership to outsiders - residents and organisations with their permanent residence or headquarters in the city. A key condition for membership will be the voluntary use of one of the above services, i.e. either the purchase of green electricity from the community, or the offer to supply green electricity if the person or institution possesses its own power generation plant.
In order to increase the number of installations and the interest of city residents, the community can also offer a financial product in the form of special securities - green bonds linked to specific planned installations.
The existence of such entities is explicitly foreseen and supported by European legislation currently in effect. On the whole, it works with the idea of a “renaissance” of photovoltaics, whose reputation is still tarnished in the Czech media space by various corruption cases. With the creation of the Prague Renewable Energy Community, we are trying to promote a boom of civic photovoltaics and show its potential for the quality of life in a metropolis like Prague. It will have benefits in terms of reducing CO2 emissions and household energy savings. Moreover, thousands of buildings in Prague have the capacity to install PV panels, so it would be a shame to let this potential go to waste.
Building renovations in for the 21st century
„If there is an area where Prague is currently not making full use of its potential, it is undoubtedly in its building stock. We are talking about thousands of available areas for the installation of photovoltaics but also for the implementation of other measures. And I am not primarily referring to privately owned buildings but to those occupied by public institutions. We want to change that and send a positive message to residents that it doesn't actually have to be that complicated.“ 
Jaroslav Klusák, Head of the Energy Management Department at the Prague City Hall
The renovation of the city's building stock is something that is directly implied by the creation of the Prague Renewable Energy Community. This is simply because the unused areas that they are located on can be adapted relatively quickly and efficiently so that photovoltaic panels can be installed on them. But it's not just about them - these buildings are equally deserving of new insulation systems and the installation of new windows to prevent unnecessary heat leakage. Furthermore, they provide an ideal opportunity for green roofs. This is where the two approaches collide - renovating the building stock offers a unique opportunity for both mitigation and adaptation. Our goal is to bring buildings in the city up to 21st century standards in this way.
Pilot projects that lay the foundations of the broader initiative are already in place. For example, the project plan for the renovation of two apartment buildings at Černý Most, which should become a benchmark for all subsequent projects and thus witness the founding of the Prague Renewable Energy Community. The renovations are expected to be completed by the end of this year.
Another example is the renovation of the Postupická Gymnázium in Prague 4, where energy saving measures are combined with the installation of a photovoltaic system (i.e. mitigation measures) supplemented by a green roof and landscaping (adaptation measures).
These are undoubtedly the forerunners, but they indicate the direction we want to take in renovating the building stock in the city.
New construction as an opportunity for the city of short distances
In view of the expected further growth in the city's population, which is anticipated to exceed the threshold of 1.4 million people by 2030 (i.e. about 100,000 more than in 2020 and about 150,000 more than in 2010), it will be necessary to continue the construction of new housing and buildings providing public amenities in the city. New construction would effectively mean additional energy requirements in all forms, from higher electricity consumption, fuels used to cover heating needs, to the energy requirements of the transport vehicles that new residents will use.
A rough estimate is that each additional inhabitant of the city can increase Prague's energy needs by an additional 15-20 MWh per year and increase the CO2 emission burden by 5-6 tonnes. With a sensible approach to spatial planning and thoughtful construction of buildings, it is possible to achieve a substantial reduction of these factors - and what is more, to transform the transport, social, and economic conditions through new construction projects in affected parts of the city in a way that fulfils the motto of the city of “short distances“.
The Climate Plan proposes that new development projects of a certain size should have a carbon footprint assessment in place at a stage where the City can influence them. It also recommends the adoption of regulatory and incentive tools which would ensure that new development within the City already have a zero-carbon footprint at the stage of its operation over the standard life cycle (at least 20-30 years) by 2025 at the latest. If this cannot be objectively achieved for a building, an available solution is to follow the progressive example of London and allow investors to acquire 'carbon offsets' that would fund climate-friendly measures in other areas.
From the same year (2025), we propose to begin assessing the carbon footprint of new construction in the city throughout its entire life cycle, including emissions from the production of the building materials used, the construction itself, and finally the demolition and disposal of construction debris. And again, the intention is to adopt incentive and regulatory instruments that will reduce the overall carbon balance to the necessary minimum.
Carbon footprint of the heating industry
„If we were now to mindlessly cut Prague off from the supply of high-emission heat, it would be very difficult to find a viable, immediately available alternative. They may be solutions on the long run, but available analyses of the potential of wastewater or more climate friendly adaptation of existing waste incineration plants show that this may be the solution we are looking for. Our challenge is to explore these options while we gradually phase out coal.“ 
Tomáš Voříšek, Head of the Working Group on Sustainable Energy and Buildings
Reducing the carbon footprint of the heating industry means first and foremost changing the current primary energy sources used for district heating. More than 90% of the (purchased) heat supply today comes from fossil fuels, primarily coal. If the carbon footprint of the heating sector is to be reduced, it is crucial to find a replacement for coal by 2030.
As Prague does not own the district heating infrastructure in the city, it has limited options for “greening” the future energy mix in the heating industry of its own volition. However, this does not mean that there are no options. More heat (in the lower hundreds of TJ per year) can be supplied to the SZT in Prague from the incineration plant of ZEVO Malešice. It is currently undergoing a major ecological transformation, which will enable it to produce heat and electricity with greater efficiency and also in larger quantities (the processing capacity for usable waste will be increased to 400 thousand tonnes/year).
The second potential heat source with a lower carbon footprint is the low-potential heat contained in the (treated) wastewater released into the Vltava River by the Central Wastewater Treatment Plant. The production output of this further usable energy reaches such a volume, that with the help of large-capacity heat pumps it would be possible to obtain thermal energy with a continuous output of 150 to 200 MW. This would allow to cover the heating needs of up to half of the households in Prague that use district heating today. It is therefore a potential heat source several times larger than ZEVO Malešice.
Environmental accounting and Prague’s carbon budget
We do not claim that all the changes we strive for will be implemented immediately. That is not within the capacity of any administration, no matter the effort put in. But if we want our approach to be systematic and evolve over time without risk of stagnation, we need to equip ourselves with effective tools to do so. That is why we supported the idea of an annual carbon budget, because it will subject our intentions to public scrutiny and allow us to learn from our mistakes in order to avoid repeating them.
The first step towards introducing environmental accounting into the city’s financial management is to put together an “individual” carbon budget for the city which will be formed from the amounts of purchased/used energies in their respective formats which are regularly financed from the city budget. The background will be provided from invoices for electricity, gas, and heat for the previous term which will then be calculated and converted into CO2 with the help of strictly defined emission factors.
- A complete system of data collection concerning the consumption and production of electric power which can be utilised to propose measures to improve the energy performance and reduce the carbon footprint of the capital city.
- Complex and unified preparation of investment projects across the different departments of the City Hall which conform to 21st century standards of building renewal (rainwater utilisation, installation of RES and their maximum use in the building itself of those neighbouring it, importance of savings, indoor air quality, maximum synergies of EPC projects and complex renewals, etc.).
- Regular evaluation of reached energy savings and increasing RES production – presentation of pilot projects aimed towards city districts and other sectors (family homes, etc.) and their replicability.
- Establishment of a revolving fund based on the evaluated savings which would support further projects utilising RES (interest-free loans for city or residential buildings, sufficient funds for pre-project planning, etc.)
- Expanding the Clean Energy for Prague project with measures focused on adaptation, higher use of RES, progressive renewal with low or passive energy standards, and others, including financial aid for pre-project and project planning.
- Providing complete consultation services for residents (partially financed through the revolving fund) in the field of renewal of residential and apartment buildings (so-called One Stop Shop) including financial support in applying for national subsidies.
- Transfer of modern technologies and processes in sustainable energy into practice in public administration of the Prague City Hall, primarily in supporting new partnerships in international projects (HORIZON 2020, etc.).
- Education in the field of sustainable energy, community renewable energy sources, and adaptation measures – regular events bridging culture and education in low carbon technologies.
Through systematic energy management, the city intends to save a large part of its energy expenditure, which should reach hundreds of million CZK annually, if all the above-listed measures and recommendations are applied within the city area.
In light of the need to monitor the carbon footprint throughout its life cycle, it should become the standard that one of the evaluation criteria should always be CO2 emissions monitored by the "LCA" method (i.e. life cycle approach). An alternative option is to require “economic viability” as an evaluation criterion for these types of investments and to convert the quantified aggregated CO2 emissions into monetary terms using an implicit unit price. In addition, minimum qualification requirements could be introduced for suppliers of various goods and services purchased by the city, for example delineating or favouring how the supplier assesses its carbon footprint and whether they actively reduce it.
Graph: carbon footprint of Prague in 2010 (form of energy supplied to the city): 
Graph: Prague's carbon footprint in 2010 (consumption sector in the city): 
Graph: Projected evolution of the city's carbon footprint (to meet climate targets) 
For those institutions that (for technical or financial reasons) cannot reduce their carbon footprint to the required extent as part of their activities or investments in the city, Prague should introduce a system of carbon offsets by enabling the acquisition of (certified) reductions from other, more cost-effective activities. For example, building zero-carbon buildings with the help of an offset mechanism has proved successful abroad (see London mentioned above). Another form of the same mechanism is the possibility to issue (authorised) units of CO2 emission reductions from defined activities of the city and city organizations and then offer these to interested local companies and citizens for purchase, thus enabling them to contribute to the city's climate goals.