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Building
Improving energy efficiency of the building stock in a city needs strategic and long-term thinking. Complex ownership structures, market barriers, diversity of building typologies, consumer preferences and multiple stakeholders involved makes energy efficient retrofitting a big challenge.
Affordable And Clean Energy
Industry, Innovation And Infrastructure
Sustainable Cities And Communities
Description
Improving energy efficiency of the building stock in a city needs strategic and long-term thinking. Complex ownership structures, market barriers, diversity of building typologies, consumer preferences and multiple stakeholders involved in the construction and retrofitting of a building makes energy efficient buildings a challenge even with the advanced technological developments. However, to realise positive energy districts and reach the ambitious climate goals set forward by cities, zero and positive energy buildings play a critical role.
A variety of initiatives worldwide have proven that while a complex challenge, Energy Efficient Retrofitting of buildings is possible and has huge impact towards greener and more resilient cities.
Problems to be solved
Energy loss in buildings
Use of inadequate materials
Energy poverty
Transition from fossil fuels
Maketechnologiesavailable
Energy demand in buildings
Benefits
Energy efficient retrofitting of buildings has lots of environmental benefits. It decarbonises existing building stocks which in turn contribute to reaching global greenhouse gas emission goals for climate protection.
Main benefits
Reducing GHG emissions
Decreasing energy consumption in buildings
Improving energy usage efficiency
Reducing energy bills
Potential benefits
Enabling new business opportunities
Creating new jobs
Reducing operation costs
Reducing use of fossils
Enhances grid stability
Shaving peak energy demand
Increasing share of renewables
Functions
Functions help you to understand what the products can do for you and which ones will help you achieve your goals.
Each solution has at least one mandatory function, which is needed to achieve the basic purpose of the solution, and several additional functions, which are features that can be added to provide additional benefits.
Mandatory functions
Reduce building energy demand
Reduce the heating and cooling needs of buildings
Improve living comfort
Maintain thermal comfort level
Potential functions
Maximise use of local renewable energy generated
Maximise use through local demand forecasts
Increase local renewable energy generation
Incorporate local renewable energy generation
Maintain good Indoor Air Quality
Maintain optimal air renewal rate
Encourage energy efficient user behaviour
Use of active and passive technologies to drive energy efficient behaviours
Variants
From a technical perspective, the possible retrofitting measures are vast and can vary according to budget and intended goal. They include, but are not limited to, insulation of the thermal envelope, change of windows, partial or total refurbishment of the heating and hot water systems, and installation of PV panels.
From a building perspective however, the differences in the decision-making process and engagement initiatives arise from the difference in building types. Depending on the building type, the refurbishment approach varies, when considering a refurbishment programme on a city level.
The different categories of building types are given below.
Once the building type has been defined, the following technical structures can be considered to improve the energy efficiency of the buildings.
1) Building Envelopes: Building envelopes and deployed insulation are key factors for the energetic behaviour of a building. Higher insulation levels usually lead to higher energy efficiency of buildings i.e., a lower heat demand.
2)Ventilation Systems: Ventilation in a building plays an important role for ensuring the wellbeing of its residents. Ventilation systems can be separated into active systems (e.g. mechanical ventilation such as fans), and passive systems (e.g. using the chimney effect). While active systems use additional energy to move air, some passive systems might require the supply of minimal energy (e.g. for opening/closing windows). Higher insulated buildings cannot only rely on natural ventilation but usually require additional ventilation systems.
3) Heating and Cooling Technologies: The new building regulations adopted by the EU encourage design of buildings that require little energy for space heating and cooling. While several new technological developments minimise the need for space heating and cooling, most buildings still need active systems such as heat pumps, district heating/cooling, solar thermal systems, CHP plants, absorption refrigerators, and vapour compression refrigeration systems, to ensure comfort and health of the occupants.
4) Energy Management Systems/Smart Home Systems: Smart homes and energy management systems are key technologies for the transition of buildings towards an eco-friendly state. The term “smart homes” describes buildings (mostly for residential purposes) that use digital technologies/Internet of Things to offer additional services such as the monitoring of systems, control of appliances, and optimisation of the operation of appliances (e.g. maximising the usage of onsite-PV generation). While smart homes describe the functionalities on the level of a single residential building, energy management systems (EMS) conduct the operational management of larger energy systems including multipurpose buildings or a multitude of buildings and appliances.
5) Renewable energy generation: Reducing existing building energy consumption consists of two synergistic approaches: (i) to reduce the need for energy through implementation of energy efficiency measures and (ii) to offset the remaining building energy needs through use of renewable energy systems, as illustrated in the figure below (Sheila J. Hayter, 2011).
Demonstration of how combining energy efficiency and renewable energy strategies significantly reduce total building conventional energy use (National Renewable Energy Laboratory)
As stated by (Sheila J. Hayter, 2011): “Renewable energy resources commonly used for building applications include solar, wind, geothermal, and biomass. Before selecting an appropriate renewable energy technology to apply to an existing building retrofit project, it is important to first consider a number of factors. Examples of these factors include:
Available renewable energy resource at or near the building site,
Available area for siting of the renewable energy technology,
Cost of energy purchased versus investment for in sitio generation,
Local regulations affecting renewable energy systems,
Desire to preserve or not alter existing architectural features,
Characteristics of the energy profiles to be offset by the renewable energy installation, etc…”
Description
Cities own, manage, or lease several buildings such as city halls, government offices, hospitals, schools, libraries, museums, social housing, etc. The city council has a high degree of control over such buildings. Ambitious energy efficiency programmes in these buildings can serve as a model for private buildings and inspire citizens to act.
Supporting City Context
The business model used is an ESCO model, where a local Natural Gas provider acts as an energy services company. In this model the end customer will have a single interlocutor, which manages and coordinates all the agents needed to execute the energy rehabilitation. This company has been offering Energy Services contracts to commercial and industrial customers for several years, including several sports centres in Barcelona, making this project highly replicable for future clients.
Use Cases
Energy
Building
Energy efficient refurbishment of tertiary residential buildings in Valla Torg, Stockholm
Under the GrowSmarter project, the City of Stockholm has implemented several energy retrofitting actions in 6 tertiary buildings from 1961 in Valla Torg to decrease energy consumption by 60%, improve indoor comfort and also extend the lifespan of the buildings.
Energy efficient refurbishment of a residential building - Brf Årstakrönet
Under the GrowSmarter project, this measure focusses on energy efficient refurbishment of a residential building from 2007: Brf Årstakrönet, with 56 private condominiums.
Energy efficient refurbishment of the building - Educative centre Escola Sert
Gas Natural Fenosa has implemented energy refurbishment of an Educative center Escola Sert. The aim is to validate the technical and economic feasibility of adding renewable energy generation to a tertiary building in the form of building integrated photovoltaics (BIPVs) for self-consumption.
Energy efficient refurbishment of tertiary buildings by the City of Stockholm
The City of Stockholm has implemented energy retrofitting actions in 2 tertiary buildings: a cultural central and an official complex. Both the buildings are named as cultural historical
Energy efficient refurbishment of tertiary buildings by Barcelona Municipality
Barcelona Municipality has retrofitted two old textile factories, lately abandoned or used as a warehouse. The buildings have been transformed into a new public library (Library Les Corts) and an R&D centre for Smart cities hosting both public and private entities (Ca l’Alier).
Energy efficient refurbishment of the building - Sports Centre CEM Claror Cartagena
Naturgy has implemented retrofitting actions to lower the energy consumption in over 12,500 m2 of tertiary floor in Barcelona. Three buildings with very different uses have been retrofitted, and one of them is a Sports Centre, CEM Claror Cartagena.
Energy efficient refurbishment of the building - Hotel H10 Catedral
Under the GrowSmarter project, Gas Natural Fenosa has implemented energy refurbishment of three buildings with very different uses , and one of them is a hotel H10 Catedral. The aim is to validate the technical and economic feasibility of executing an energy refurbishment of a tertiary building.
Energy efficient refurbishment of residential buildings by Naturgy
Naturgy has implemented retrofitting actions with the aim of lowering the energy consumption of buildings in nearly 20,000 m2 of residential floor in Barcelona: Canyelles, Ter, Lope de Vega and Melon District.
Energy efficient refurbishment of a residential building - Passeig Santa Coloma
Barcelona Municipality has promoted the energy refurbishment of a social housing building in Passeig Santa Coloma with 207 dwellings and over 14,000 m2.
'Living' Energy Efficient Apartment Complex in Torino
In response to worsening heatwaves in Torino, Italy, the 25 Verde building was built incorporating over 150 trees and plants along with energy efficiency measures, to create a unique living space that both addresses climate change adaptation needs and represents mitigation potential.
Energy Efficiency & CO2 Saving in the City of Antwerp
The City of Antwerp used a power quality improvement system, called E-Power, to improve energy efficiency and reduce consumption in eight of its public buildings, with potentially more to come.
Retrofitting Old Soviet Apartment Buildings in Tartu
As part of the SmartEnCity project, the objective of the retrofitting is to drastically reduce the energy usage of the old Soviet era buildings, khrushchyovkas, by around 70%. Several energy saving measures have been undertaken to reach this goal.
Milan aims to address deep energy retrofit of the residential building stock, both public and private, to save up to 60-70% of current energy consumption and improve comfort inside dwellings.
Aiming to achieve a sustainable districts in Tepebasi through deep retrofitting, the improvements in building envelope's designs were implemented. Minimizing heat transfer through the building envelope is crucial for reducing the need for space heating and cooling.
With the aim of achieving a Near Zero Energy District in Valladolid, a series of interventions have been designed focusing on improving the sustainability of the 19 residential buildings of the FASA neighbourhood, increasing its energy efficiency and reducing the CO2 emissions of its buildings.
Energy Retrofitting Through Public Procurement in Nottingham
A UK council housing estate with a high density of fuel poverty has benefited from an energy makeover which bundles technology, aesthetics and a novel approach to public procurement.
Public Art Gallery on Retrofitted Apartments in Tartu
Tartu organized an international art competition to make its pilot area for turning Khrushchev-era buildings into modern energy efficient homes, creating an attractive and unique urban environment for its citizens to enjoy.
Social housing is owned and managed by public authorities or non-profit organisations or a combination of two with the aim of providing affordable housing to the citizens. In addition to alleviating fuel poverty, retrofitting social housing may also improve public health. The main goal in this case should be to improve comfort while maintaining or reducing costs.
Supporting City Context
The project Lorystraße 54-60 is a medium-size housing block with 95 flats, completed in 1966 and owned by ‘Wiener Wohnen’ the city-owned social housing operator. The thermal refurbishment reduced the heat energy demand by more than 80 percent. Additionally, a 9 kWp PV-System was installed.
Use Cases
Energy
Building
Refurbishment of a Municipal Housing Estate in Vienna (Social Housing Lorystraße 54-60)
The project Lorystraße 54-60 is a medium-sized housing block with 95 flats, completed in 1966 and owned by ‘Wiener Wohnen’, the city-owned social housing operator. The thermal refurbishment reduced the heat energy demand by more than 80 percent. Additionally, a 9 kWp PV-System was installed.
Refurbishment of a Municipal Housing Estate in Vienna (Social Housing Herbortgasse 43)
The municipal housing estate in Herbortgasse 43 was built in 1929 and is under heritage protection. The thermal refurbishment of the façade reduced the heat energy demand by about 75 percent, from 118 kWh/m²yr to approximately 28 kWh/m²yr. 8 additional flats were constructed in a rooftop extension.
Refurbishment of a Social Housing Rental in Vienna
The project ‘Hauffgasse 37-47’, completed in 1987, is a large housing block with 485 flats. It is supplied by a micro-district-heating-grid and currently fired with natural gas. The objectives were mainly focusing on the reduction of energy demand and the integration of renewable energy sources.
Public authorities own and operate a small share of the buildings in the city. As such, to reach ambitious energy and climate goals, it is essential to encourage residents and commercial organisations to undertake energy retrofitting projects. There is a need to create awareness about the suitable policy measures and financial incentives among the final decision makers: the residents and commercial organisations. For most individuals and organizations, undertaking energy efficiency refurbishment is a big and important decision considering the high and long-term investment.
Supporting City Context
In the Piemonte region in Italy, where Torino is located, maximum temperatures have risen by 2°C in the last 60 years, with extreme heatwaves projected to continue to increase in the coming century due to global climate change. Buildings, therefore, need to be more resilient to heat, while decreasing their contributions to fossil fuel emissions and urban heat island effect. The project was awarded a 20% discount on construction taxes due to the environmental benefits it provides.
Use Cases
Building
Energy
'Living' Energy Efficient Apartment Complex in Torino
In response to worsening heatwaves in Torino, Italy, the 25 Verde building was built incorporating over 150 trees and plants along with energy efficiency measures, to create a unique living space that both addresses climate change adaptation needs and represents mitigation potential.
The urgency to deal with the energy efficiency of buildings is enormous. The EU also recognizes this and there are several standards on the energy efficiency of buildings at EU level. Several legislative initiatives have been introduced for building renovation, the most important ones are given below:
Energy Performance in Buildings Directive (EPBD, Directive 2010/31/EU amended by Directive 2018/844/EU)
Energy Efficiency Directive (EED, Directive 2012/27/EU amended by Directive 2018/2002/EU)
Directive of 16 December 2002 on the energy performance of buildings
Directive of 6 July 2005 establishing a framework for setting eco-design requirements for energy-using products
Directive of 5 April 2006 on energy end-use efficiency and energy services
Directive of 23 April 2009 on the promotion of the use of energy from renewable sources providing for the promotion of energy efficiency
Directive of 21 October 2009 establishing framework for setting Eco-design requirements for energy-related products
Directive of 19 May 2010 on the indication of energy efficiency labelling and standard product information on the consumption of energy and other resources by energy-related products
Directive of 19 May 2010 on the energy performance of buildings
Since member states had to integrate these directives into national law, there are many standards regarding energy efficiency in the EU on the national level differing from country to country. Some examples of regulations and standards regarding energy efficiency are listed below (United Nations Economic Comission for Europe, Mapping of Existing Energy Efficiency Standards and Technologies in Buildings in the UNECE Region, 2018):
France: sets minimum standards for existing buildings and defines the necessary renovations for them.
Switzerland: the renovated building must not exceed 125% of the new building's energy limit.
Denmark: Solar heating systems must be provided when the expected hot water consumption exceeds 2,000l per day and can meet 95 per cent of demand.
Greece: 60% of domestic hot water is from solar energy.
Further standards of various countries can be found in the countries’ information sheets of the report of UNECE. Some regulations already mentioned in North America are:
Energy Policy Act of 2005
ASHRAE9 90.1.2007
ICC Energy Conservation 2000-201510
Vancouver’s step-by-step plan
Operating Models
Energy retrofit calls for huge initial capital investment with long payback periods. To accelerate retrofitting, favourable financing and market mechanisms, as well as innovative business models are crucial. The policy interventions highlighted in the previous section have the potential to improve access to financing, de-risk investment and reduce barriers while increasing the attractiveness of building sector investments.
While local and national governments can promote specific supporting policies, public resources can cover only a limited amount of total investments. To obtain substantial results, it is necessary to involve the private sector in financing energy-efficient refurbishments. However, financial institutions face several challenges while approaching the energy efficiency market. These include the small size, fragmentation of investments, and lack of project standardisation which cumulatively result in higher risks.
There is a variety of financing mechanisms available to and being explored by local and state governments including energy service performance contracts (ESPCs), revolving loan funds, leasing, on bill financing, and more. Some of these are explained below:
1) Revolving Loan Funds: RLFs are capital pools set aside by the local or national government from which loans can be made for energy retrofit projects. As the loans are repaid, the capital is then reloaned for another project. Assuming that defaults remain low, RLFs can be "evergreen" sources of capital that are recycled over and over again to fund projects well into the future.
2) On Bill Financing: OBF is a type of loan, introduced first in the USA, that uses the utility bill as a repayment vehicle. It helps reduce barriers like high upfront costs in retrofitting and is a possible solution for the owner tenant dilemma. The loan is paid back over time through the monetary savings on the reduced utility bill. The property owner pays the same bill before and after the renovations and the difference due to savings goes to the investor.
3) Energy Performance Contracting: EPC is a form of financing for capital improvement which enables funding of energy upgrades from cost savings. Under an EPC arrangement an external organisation (ESCO) implements a project to deliver energy efficiency, or a renewable energy project, and uses the stream of income from the cost savings, or the renewable energy produced, to repay the costs of the project, including the costs of the investment (European Commission, 2020).
A key component of successful green retrofit finance programs is the concept of the “cash positive” financial model. This refers to having financial mechanisms which reduce the risk and burden from property owners by ensuring savings right from the first month. The financial arrangements should have interest rates that ensure that the monthly utility bill is reduced by an amount greater than or equal to the monthly repayment instalments providing immediate and steady returns. It has to be noted that legal aspects and underpinnings of various financial models vary greatly across state and local governments. It is essential to conduct rigorous due diligence to clearly understand what types of financing models can be deployed in your community.
Cost Structure
Fixed Costs
Variable Costs
Manpower
Material
Administrative costs
Transportation
Tenant engagement activities
Equipment
Communication
Utilities (Energy & Water)
Fees & Taxes
Cost Structure for Energy Efficient Retrofitting of Buildings (BABLE, 2021)
A good reference for costs can be found in the Use Case from Vienna. The initial investments for interventions in 95 flats over 50 years old, was about €4,3 million, which accounts for €680 per m² of useable surface and contained the costs for thermal refurbishment works, maintenance works, and works to increase housing comfort.
The thermal refurbishment of the façade reduced the heat energy demand by more than 80 percent, from 130 kWh/m²yr to approximately 23 kWh/m²yr. Additionally, a 50 m² large PV-System with 9 kWp was installed on the roof.
The total cost of €4,3 million was reduced by direct grants and annuity grant and the annual rent-income of €2.55 million (for 6.330 m² useable surface = €3,35 per m² per month) is used for the payback of the investment (BABLE, 2019).
Market Potential
The Energy Efficient Retrofitting market for buildings has enormous potential since 75% of the building stock in Europe is considered energy inefficient. On a global scale, this number might even be worse, generating an interesting gap to cover with refurbishment initiatives.
Stakeholder Mapping
Stakeholder Map for Energy Efficient Retrofitting of Buildings (BABLE, 2021)
Government Initiatives
Local and national governments need to make clear commitments to ensure long-term market signals towards energy efficient technologies. The accelerated uptake of energy efficient technologies will require a push and pull policy approach. On one hand, mandatory performance targets that push building owners to adopt energy efficient technologies. On the other hand, upfront incentives such as consumer rebates, which reduce barriers such as high upfront costs and higher cost of energy efficient products.
The following list provides examples of some policy measures that can be adopted:
Legislative
Design building codes and standards that encourage the delivery of deep renovation and regularly strengthen them in response to new technological developments. Strive for near-zero emissions in new construction.
Set Minimum Energy Performance Standards for energy use equipment.
Introduce quality standards/certification systems for installers and products.
Identify restrictive tenancy laws which disincentivise or inhibit energy performance improvement and update those laws to support sustainable transition.
Set minimum on-site renewable energy production limits in order to promote the local implementation of renewable energy sources and to utilize the existing local sustainable energy potential (an example of legislative action to use at least a certain share of the roof area for PV can be found here).
Streamline the design of sustainable energy concepts by starting the process at the beginning of the planning phase of the transition process. Thereby, the district development process can be influenced by the energy concepts towards positive energy districts and energy saving and self-sufficiency potentials can be utilized more easily (avoiding disadvantageous path-dependencies in the planning process).
Technical
Ensure minimal or no lock-in of inefficient and carbon-intensive technologies in all new constructions during the planning approval phase (e.g. prioritising connection to district heating/cooling network).
Simplify and enable deployment of high-efficiency, low carbon technologies such as electric heat pumps and solar thermal units.
Promote use of advanced controls, such as energy management systems and smart home technologies for energy efficient behaviour.
Address challenges concerning local deployment of low/zero carbon technologies.
Ban energy intensive and polluting technologies that are reliable on fossil fuels (e.g. incandescent and halogen light bulbs, electric resistance heaters, oil boilers etc.).
Mandate the usage of waste heat from large scale plants for on-site or district systems.
Promote the development of integrated energy concepts that incorporate various building types, sectors and energy demand to maximize the utilization of (energetic) synergies
Financial
Develop funding vehicles tailored to specific market segments that provide simple and commercially attractive source of finance for deep renovation.
Develop mechanisms to encourage deep renovation via third party financing e.g. ESCOs and EPCs
Strengthen carbon pricing mechanisms to provide the right economic signals.
Incentivise deep energy retrofitting of existing building shells (e.g. reduce property tax for high energy performing buildings).
Incentivise adoption of renewable energy and energy efficient technologies.
Worldwide there have been interesting movements happening towards increasing the efficiency of buildings. The European Union seems to be in the vanguard of the movement, with several directives published aiming towards climate neutrality. Among them are specific directives for Energy Performance of buildings, frameworks for setting requirements for materials and design, and for promotion of renewables.
While in the United States, the Energy Policy Act of 2005 covers almost every aspect of energy generation, distribution, and consumption, along with guidelines on energy efficiency. In 2012, 31 USA states, by adopting either ASHRAE9 90.1.2007 or the ICC Energy Conservation 2000-2015, implemented model codes for residential and commercial buildings, in Canada there is the Vancouver’s step-by-step plan to promote the uptake of highly energy efficient buildings by removing barriers to Passive House is linked to Vancouver’s Greenest City Action Plan (UNECE, 2019).
In countries like Serbia, Kazakhstan, Belarus, Russia and some others, the governance structure is such that building codes are made at the federal level, without an option for regional governments to choose whether to adopt the codes or not. In such cases, regions are able to prepare and submit additional design and construction norms or procurement procedures requirements, which will reflect the regional specifics, but will not contradict the federal level law. This situation does not allow the codes to be updated more frequently considering the technological developments in the building sector. The regulatory bodies of these countries acting at the federal level are currently focusing on the implementation of performance-based building codes with minimum energy standards rather than prescriptive building codes. This will give building contractors and owners the flexibility to choose the best technological option to reduce energy consumption (UNECE, 2019).
Supporting Factors
Percentage share of buildings in the EU in different EPC classes (Buildings Performance Institute Europe, 2017)
To achieve carbon neutrality , it is essential to consider both the future buildings being built, and the existing building stock, which constitutes a majority of the buildings we live in today and onwards. As already mentioned, approximately 75% of the European building stock is considered as not energy efficient, i.e., not reaching at least EPC class C, as shown in the figure above, while the figure below gives this distribution on a country basis.
Distribution of the building stock in theEU per EPC class (Buildings Performance Institute Europe, 2017)
The lifetime of European buildings ranges from 40 - 120 years. To reach the ambitious climate and energy goals set by the European Union and demanded for mitigating climate change, the majority of the building stock in the EU needs to be at least nearly zero-energy (Dorizas, Groote, & Fabbr, 2019). Consequently, renovating buildings is a crucial aspect of meeting the European energy efficiency and CO2 emission reduction targets. For the decarbonisation of the building sector, three central pillars are recommended by the International Energy Agency (IEA, 2020):
1) Sufficiency: This deals with interventions in design stage. Energy demand in buildings should be minimized while providing same or improved level of comfort. This will focus on reducing energy need using innovative design, materials and other similar measures that lead to passive buildings.
2) Efficiency: Improving performance of building technologies through facilitation adoption of energy-efficient solutions through policy and market frameworks. This would also include investing and promoting research and innovation in highly energy efficient technologies.
3) Decarbonisation: Once the energy demand for buildings is minimized by using sufficiency and efficiency measures, the remaining low energy demand should be satisfied with high performance, low-carbon solutions.
City Context
It is estimated that people spend on average 85-90% of their time indoors either in their home, in school, at work, or during leisure time. To ensure a high level of comfort, buildings across the globe are fitted with different technologies to heat or cool space, provide clean and hot water, fresh air and electricity to power appliances that simplify human life.
As per the International Energy Agency (IEA), buildings and building construction sectors combined are responsible for one-third of global final energy consumption and almost 40% of total direct and indirect CO2 emissions and hence are a source of enormous untapped efficiency potential (IEA, 2020).
Global Urban Primary Energy Use and CO2 Emissions
According to the European Commission estimations, almost 75% of Europe’s building stock is currently energetically inefficient, and the annual renovation rate ranges from just 0.4 to 1.2%, depending on the country. The inefficiency of buildings in terms of energy and resource use constitutes a large societal challenge in connection to our total consumption and CO₂ footprint. This adds pressure on the total integrated energy and city system (State of Green, 2020). Thus, building efficiency plays a decisive role in supporting cities to achieve their carbon neutrality targets. Buildings generate direct CO2 emissions through fuels that are burned (e.g. oil, natural gas) and indirect emissions through the use of fossil fuel powered electricity that is used in the buildings (IEA, 2019). The figure above shows the share of buildings in urban primary energy use and CO2 emissions, relative to global levels.
The creation of this solution has been supported by EU funding
Use Cases
Energy
Demand Side Response (DSR) Control for Student Accomodation
The use case aims to deliver strategic load curtailment in student accomodations via existing BEMS.
Within the GrowSmarter project."Smart local thermal districts" is part of the building refurbishment in Ca l’Alier, which combines on-site electricity generation (PVs) with the local existing DHC network, reducing the consumption of fossil primary energy for heating and cooling production.
Smart control of individual rooms in existing buildings
With the aim of reducing energy consumption by 20% in the existing office buildings in Strijp-S, an innovative concept has been developed to optimise energy consumption while maintaining user comfort. The system allows interactive monitoring and control of HVAC system via mobile application.
Retrofitting Old Soviet Apartment Buildings in Tartu
As part of the SmartEnCity project, the objective of the retrofitting is to drastically reduce the energy usage of the old Soviet era buildings, khrushchyovkas, by around 70%. Several energy saving measures have been undertaken to reach this goal.
To improve energy efficiency of existing residential buildings by 70% as part of EU Horizon 2020 GrowSmarter Project, renovation measures were undertaken. This includes building envelope insulation, high efficient windows, staircase lighting, elevator and heating system.
Energy efficient refurbishment of tertiary residential buildings in Valla Torg, Stockholm
Under the GrowSmarter project, the City of Stockholm has implemented several energy retrofitting actions in 6 tertiary buildings from 1961 in Valla Torg to decrease energy consumption by 60%, improve indoor comfort and also extend the lifespan of the buildings.
Energy efficient refurbishment of tertiary buildings by the City of Stockholm
The City of Stockholm has implemented energy retrofitting actions in 2 tertiary buildings: a cultural central and an official complex. Both the buildings are named as cultural historical
Energy efficient refurbishment of a residential building - Brf Årstakrönet
Under the GrowSmarter project, this measure focusses on energy efficient refurbishment of a residential building from 2007: Brf Årstakrönet, with 56 private condominiums.
Milan aims to address deep energy retrofit of the residential building stock, both public and private, to save up to 60-70% of current energy consumption and improve comfort inside dwellings.
Energy efficient refurbishment of tertiary buildings by Barcelona Municipality
Barcelona Municipality has retrofitted two old textile factories, lately abandoned or used as a warehouse. The buildings have been transformed into a new public library (Library Les Corts) and an R&D centre for Smart cities hosting both public and private entities (Ca l’Alier).
Energy efficient refurbishment of the building - Educative centre Escola Sert
Gas Natural Fenosa has implemented energy refurbishment of an Educative center Escola Sert. The aim is to validate the technical and economic feasibility of adding renewable energy generation to a tertiary building in the form of building integrated photovoltaics (BIPVs) for self-consumption.
Energy efficient refurbishment of the building - Hotel H10 Catedral
Under the GrowSmarter project, Gas Natural Fenosa has implemented energy refurbishment of three buildings with very different uses , and one of them is a hotel H10 Catedral. The aim is to validate the technical and economic feasibility of executing an energy refurbishment of a tertiary building.
Energy efficient refurbishment of the building - Sports Centre CEM Claror Cartagena
Naturgy has implemented retrofitting actions to lower the energy consumption in over 12,500 m2 of tertiary floor in Barcelona. Three buildings with very different uses have been retrofitted, and one of them is a Sports Centre, CEM Claror Cartagena.
Energy efficient refurbishment of residential buildings by Naturgy
Naturgy has implemented retrofitting actions with the aim of lowering the energy consumption of buildings in nearly 20,000 m2 of residential floor in Barcelona: Canyelles, Ter, Lope de Vega and Melon District.
Energy efficient refurbishment of a residential building - Passeig Santa Coloma
Barcelona Municipality has promoted the energy refurbishment of a social housing building in Passeig Santa Coloma with 207 dwellings and over 14,000 m2.
Aiming to achieve a sustainable districts in Tepebasi through deep retrofitting, the improvements in building envelope's designs were implemented. Minimizing heat transfer through the building envelope is crucial for reducing the need for space heating and cooling.
With the aim of achieving a Near Zero Energy District in Valladolid, a series of interventions have been designed focusing on improving the sustainability of the 19 residential buildings of the FASA neighbourhood, increasing its energy efficiency and reducing the CO2 emissions of its buildings.
Energy Retrofitting Through Public Procurement in Nottingham
A UK council housing estate with a high density of fuel poverty has benefited from an energy makeover which bundles technology, aesthetics and a novel approach to public procurement.
Refurbishment of a Social Housing Rental in Vienna
The project ‘Hauffgasse 37-47’, completed in 1987, is a large housing block with 485 flats. It is supplied by a micro-district-heating-grid and currently fired with natural gas. The objectives were mainly focusing on the reduction of energy demand and the integration of renewable energy sources.
Refurbishment of a Municipal Housing Estate in Vienna (Social Housing Lorystraße 54-60)
The project Lorystraße 54-60 is a medium-sized housing block with 95 flats, completed in 1966 and owned by ‘Wiener Wohnen’, the city-owned social housing operator. The thermal refurbishment reduced the heat energy demand by more than 80 percent. Additionally, a 9 kWp PV-System was installed.
Refurbishment of a Municipal Housing Estate in Vienna (Social Housing Herbortgasse 43)
The municipal housing estate in Herbortgasse 43 was built in 1929 and is under heritage protection. The thermal refurbishment of the façade reduced the heat energy demand by about 75 percent, from 118 kWh/m²yr to approximately 28 kWh/m²yr. 8 additional flats were constructed in a rooftop extension.
Refurbishment of Secondary Schools and a Public Gym into Zero-Energy
The refurbishment of a public gym and the addition of 16 class rooms to the schools serves as a testbed for the use of new energy solutions. It is a pilot project testing climate friendly smart city solutions. The current energy performance of 104 kWh/m2 is reduced to 27 kWh/m2.
Public Art Gallery on Retrofitted Apartments in Tartu
Tartu organized an international art competition to make its pilot area for turning Khrushchev-era buildings into modern energy efficient homes, creating an attractive and unique urban environment for its citizens to enjoy.
Energy saving, CO² reduction & optimisation of the indoor climate of a court house building in Tallinn
Satisfaction of the building's tenants and visitors is one of the top priorities. The indoor climate has improved since R8 Autopilot started to control the building in November 2019.
Energy Saving, CO² Reduction & Optimisation of the Indoor Climate of an Office Building in Coimbra, Portugal
Satisfaction of the building's tenants and visitors is one of the top priorities. Since R8 Autopilot started to control the building, the indoor climate has improved and the energy and CO² emissions were reduced.
Approximately one-quarter of the energy price is owed by the transportation of the energy. The implementation of a local energy system can shift the energy production from a centralised system to a decentralised system.
An intelligent and connected public space collects data in public areas and displays or reacts on the data. The data can be securely transferred via Wi-Fi or other similar technologies to be, i.e. combined with a central system.
According to the Energy Performance of Buildings Directive (EPBD), buildings are responsible for approximately 40% of energy consumption and 36% of CO2 emissions in the EU.
The majority of public funding for energy efficiency within the EU is proposed in the building sector. The federal funds for energy efficiency in residential buildings added up to €97 million in 2019. A Smart Home System is one possibility to improve residential energy efficiency.
The supply of energy to households, public buildings and services accounts for the majority of GHG emissions in the majority of municipalities. Municipal Energy Saving Systems represent punctual solutions to optimise energy consumption.