Financing

Public and public-private financing approaches such as preferential loans, revolving funds and government-facilitated third-party financing aim at tackling the financial barrier to energy efficiency investments, specifically their high up-front costs. By providing opportunities for building owners to either get access to low interest loans and/or to benefit from innovative loan repayment mechanisms they increase the attractiveness of energy efficiency investments and thus promote the implementation of energy-efficient building concepts (such as Low-Energy Buildings and better Ultra-Low-Energy Buildings, cf. the bigEE Strategic Approach in our Buildings Guide) and technologies.

Worldwide implementation status
Energy efficiency financing schemes are being implemented all over the globe (see for instance Taylor et al. 2008; Maio et al. 2012; Kats et al. 2012 as well as the examples mentioned in the Summary here under Key information, and the bigEE Good practice examples).

Governance level
Existing energy efficiency financing schemes can be found mostly on a national, regional or local level, but also on a trans-national level (e.g. the European Energy Efficiency Fund).

Related sectors

• residential
• services
• industrial

Concepts

• Low-Energy Buildings
• Ultra-Low-Energy Buildings
• nearly-Zero-Energy / Plus-Energy Buildings

Options

• Thermal comfort
• Microclimate
• Building Form
• Building envelope
• Shading
• Passive cooling techniques
• Passive solar heating

• Mechanical ventilation
• Cooling
• Heating
• Domestic Hot Water
• Lighting
• Street Lighting/Traffic lights
• Building transportation
• Building integrated renewable energy systems

Behaviour and Management

• Building Energy Management
• Design Optimisation

The main target group of financing instruments are investors on the demand side such as landlords, housing companies and investor-occupiers. Through the provision of financial incentives inherent in different financing schemes these actors shall be motivated to mobilise private capital and to make investment decisions into energy efficiency projects.

Related target groups

• Property development company: Financing schemes target property development companies via the provision of advantageous financing opportunities (for property development companies themselves or their customers to whom they sell buildings or apartments) to encourage them to consider energy-efficient building designs within their business decisions for new buildings or redevelopments.
• Investor: In exchange for the financing, investors are expected to modify their investment towards higher energy efficiency.
• Investor-occupier: Investor-occupiers are also expected to modify their investment towards higher energy efficiency
• Bank: Banks are targeted in preferential loan schemes by means of providing financial incentives (i.e. cause-related low interest credits or subsidies or partial/full credit default guarantees) to get them engaged in lending to investors in energy efficiency measures.
• Energy company: Energy companies may offer financing schemes via the provision of easily accessible and low interest rate financing, maybe combined with a financial incentive, to support the implementation of energy efficiency measures. This may be an option to achieve their energy savings targets in the framework of an energy saving obligation scheme
• Governmental actor: Financing schemes may also target government administrations as implementers of energy efficiency measures in publicly owned property (including social housing).

Direct beneficiaries
Investors on the demand side such as landlords, housing companies and investor-occupiers benefit directly due to facilitated and advantageous ways of funding energy efficiency investments. Preferential loans or government-facilitated third party funding either reduce their own equity contribution or associated risk or both.

Indirect beneficiaries
Due to the availability of advantageous financing opportunities, implementation of energy efficiency measures is likely to increase, which translates into increased demand for related services from actors on the supply side able to offer energy-efficient solutions, including architects, construction companies, installation contractors, manufacturers of components and prefabricated houses, system suppliers as well as energy consultants and energy service companies. Moreover, also tenants and users of buildings and equipment indirectly benefit in terms of reduced energy bills, improved living comfort or working conditions.

Direct beneficiaries

• Investor

  Investors may benefit from lower interest rates, easier access to capital, or reduced financing risks

• Investor-occupier

  Investor-occupiers will benefit from lower energy bills and often from improved thermal comfort. They may also benefit from lower interest rates, easier access to capital, or reduced financing risks

• Bank

  Banks benefit particularly from financing schemes that provide partial or full loan default guarantees in that risk associated with their lending business is minimized or completely externalized.

Indirect beneficiaries

• Architect

  Architects offering very energy-efficient building designs or advice in ‘deep’ energy renovation may see an increased demand for their services.

• Construction company

  Companies able to construct very energy-efficient buildings or to realise ‘deep’ energy renovation may see an increased demand for their services.

• Installation contractor

• Manufacturer

• Manufacturer of prefabricated houses

• Property development company

• System supplier

• Tenant

  Tenants will benefit from reduced energy bills and often from improved thermal comfort.

• User

  Users are likely to benefit from improved thermal comfort in the energy-efficient buildings.

• Energy consultant

• Energy Service Company

Relevant barriers

• Knowledge and information barriers: Particularly in preferential loan schemes that are implemented as PPP arrangements, energy efficiency financing has an informational/educational impact on those responsible in the respective private financial institution. Examples of successful and economically rewarding implementation can make the case for a broader incorporation of such practices in standard business portfolios in the financial sector.
• Economic and financial barriers: By providing access to advantageous financing opportunities, the establishment of either of the aforementioned energy efficiency financing schemes addresses the financial barrier of high up-front costs of energy efficiency investments. Especially in renovation of existing buildings, there is the additional barrier of the basic renovation investment, even without an improvement to energy efficiency.
• The investor-user barrier: Intelligently designed financing schemes can help to overcome the split incentives dilemma by e.g. offering more favourable credit conditions to landlords under the condition that they only pass on a specified share of the incremental energy efficiency investment costs to tenants, which does not exceed the expected energy savings.
• Lack of interest and motivation in energy efficiency-improvement: Against the backdrop of reduced transactions costs, required equity contribution and associated risks, brought about by favourable and easily accessible financing opportunities, investments into energy efficiency measures become more attractive for investors.

Relevant incentives

• Saved energy costs: Access to energy efficiency financing schemes that offer advantageous conditions in terms of interest rate level, payback period or repayment mechanism, further increases the financial attractiveness of energy efficiency investments for investor-occupiers with regard to achievable energy cost savings vis-à-vis required up-front investment costs.
• Directly increasing earnings or profits for actors on the supply side: The establishment of energy efficiency financing schemes that offer advantageous conditions in terms of interest rate level, payback period or repayment mechanism provides property development companies with opportunities to lower their investment cost and thus increase their profit margin on sales.
• Increased (re-sale) value of the property: Higher energy efficiency will reduce energy bills and thus increase the value of the property, particularly if this becomes transparent, e.g., through Energy Performance Certificates

Although lack of or access to financing is a major barrier to improving energy efficiency in buildings (particularly for SMEs and private owners of residential buildings), providing advantageous financing opportunities alone will not be sufficient to achieve this goal. A survey commissioned by the Global Buildings Performance Network (GBPN) on the building sector’s view on energy efficiency showed that the lack of enforcement of regulations as well as skewed perceptions of the cost of building energy efficiency are major obstacles to that end (cf. Economist Intelligence Unit 2012). Thus, in order to achieve a genuine and long-term market transformation, financing opportunities should be combined with additional financial, regulatory and informational tools, such as financial incentives like tax credits or grants for implementing strong energy efficiency measures; the introduction of Minimum Efficiency Performance Standards (MEPS) and Energy Performance Certificates; advice and assistance during design and construction, training for construction workers and other supply-side actors, and the provision of education offers to financiers. This will raise awareness of the benefits of energy efficiency and further strengthen incentives for private investment.
We advise the reading of the bigEE file on the recommended policy packages for the mainstreaming of Ultra-Low-Energy New Buildings in new build and for the achievment of high energy savings in building renovation.

The following pre-conditions are necessary to implement Financing:
Agencies or other actors responsible for implementation
The implementation of financing instruments requires the nomination of an institution that is responsible for the coordination, oversight and (external) evaluation of the financing schemes. This could for instance either be an energy agency, an (revolving) energy efficiency fund, a public development bank such as the German KfW, or energy companies. In addition, there may be the need to involve retail banks, energy companies, or energy service companies to handle the loan or finance applications as well as the payments to and repayments from investors.

Funding
Substantial funding for financing schemes is needed in order to promote the development of a genuine market for energy efficiency. The initial funding for the revolving loans as well as funding for continuous programme administration and the cost of making loans preferential could stem from different sources, such as the revenues from an energy tax or an emission trading scheme or earmarked government budget allocations. Most of the investment in energy efficiency will, however, be made by building owners or energy service companies and will be repaid to the organisations offering the energy efficiency financing schemes.

• Conduct a pre-study in order to analyse the local/national market for existing financing opportunities and prevalent actor-specific barriers to energy efficiency investments as well as the associated untapped saving potential
• Define sector focus (residential, commercial, or industrial sector) and respective target group(s) of the financing scheme
• Screen state-of-the-art building design options and BAT
• Based on the results, define a set of energy efficiency improvement actions, eligible for support via the financing scheme under consideration, and their (estimated) energy savings potential. This step could also be linked to similar actions required for the preparation of setting up an energy saving obligation scheme.
• Define elements of the financing scheme including source(s) of capital, mechanism of finance delivery, collection mechanism, types of credit enhancements provided by the scheme, loan security requirements and underwriting criteria. For a more detailed listing and elaboration of the elements of financing schemes see Table 1.
• Appoint the competent authority responsible for the coordination, oversight and (external) evaluation of the financing scheme. 
• Define and engage the actors responsible for handling loans to building investors.
• Define structure and operational mode of a monitoring information system (MIS) and provide detailed guidelines to implementing actors in order to ensure the collection of valid data for evaluation purposes.
• Schedule and conduct regular (external) evaluation of scheme performance and impact in order to justify the continued use of public funds and, if necessary, adjust its specifications to respond to changes in the market (e.g. energy prices, market interest rates, new BAT asf.) or terminate it.

Source: Fuller et al. 2009

Quantified target
Each of the aforementioned energy efficiency financing schemes can have quantified targets relating to different success/performance indicators. These may be the budget which is to be provided for direct lending or indirect lending support, ex-ante specified numbers of motivated credit users or specific energy efficiency actions implemented or a combination thereof. Thinking further, these immediate indicators may then also be translated into an estimate of achievable energy savings. There may be a trade-off between high participation rates and high energy efficiency levels aimed for. Initially, a good compromise may need to be found between those two objectives. Over time, energy efficiency levels should be strengthened while maintaining high participation rates.

International co-operations
Co-operation between countries can include an exchange of information relating to experience on principles as well as practical details, problems, and solutions of implementing such financing schemes. Providing climate finance — such as the programmatic Clean Development Mechanism, New Market Mechanisms, Nationally Appropriate Mitigation Actions (NAMAs) — to developing and emerging countries for funding financing schemes is another potential way of co-operation. For example, the expansion of the Mexican Green Mortgage programme (cf. the bigEE good practice policy example) is now being co-funded through the NAMA facility of the UK and German governments with up to €14 million (http://www.mitigationpartnership.net/nama-sustainable-new-housing).

Monitoring
Monitoring the performance of energy efficiency financing schemes is essential in order to generate data on the measurable benefits of energy efficiency investments. A monitoring information system (MIS) should be an integral part of a financing scheme design and needs to establish clear specifications regarding data requirements for evaluation purposes (such as the types of energy efficiency actions financed and their energy efficiency specifications, like U-values of walls, roofs, or windows, cm of insulation material added and its thermal resistance, efficiency of heating or cooling systems, or specific energy performance of equipment or whole buildings) and provide guidelines to implementing actors on how to record the data and to assure loan recipients’ compliance with the scheme’s terms and conditions.
The data required to evaluate achieved energy savings resulting from the operation of financing schemes are more difficult to obtain. In order to assess whether a scheme for energy efficiency measures delivers significant additional energy savings, elaborate measurement and verification (M&V) is needed.
This is particularly relevant for government-facilitated third party financing schemes since repayments of investment cost for the implementation of energy efficiency measures to the financing entity have to be covered by resulting end user savings. In this instance, monitoring of household energy consumption prior to and after the implementation of financed measures, according to a metered baseline approach (cf. Bertoldi/Rezessy 2009, p.30), is indispensable. However, although providing more precise results, this proceeding entails considerable administrative effort and monetary expense, which may impede a broader roll-out of such schemes. In schemes with different refinancing mechanisms, other approaches with lower transaction costs to monitor energy savings for evaluation purposes, such as the deemed savings or the engineering approach, may thus be employed. These use ex-ante specified estimates of achievable/projected energy savings for measures that are financially promoted within a scheme. Thus, a second best solution to evaluate the impact of a financing scheme is to monitor numbers and types of energy efficiency measures that have been financed through the scheme as well as a set of building properties and then use these data to calculate overall energy savings.
With regard to the evaluation of the economic benefits and costs, information requirements for the latter include data on expenditure relating to the operation (i.e. administrative cost) of a scheme as well as data on loan performance (i.e. share of loan defaults). Equally important are the investments made by those who received the preferential loans or other financing support. It may be necessary to analyse a sample of investments to identify the full cost of new build and renovation as well as the incremental investment in energy efficiency improvement. With regard to the economic benefits of financing schemes, monitoring mainly needs to capture data on changes in end users’ energy expenditures associated with the implementation of financed energy efficiency measures.

Evaluation
Independent evaluations of publicly operated energy efficiency financing schemes are an important means of demonstrating their economic viability (also compared to alternative energy efficiency policies) and thereby not only justify the dedication of public funds but also contribute to making a case for an increased involvement of private financial institutions. Moreover, they can provide evidence regarding what measures financing schemes should best target in order to achieve the highest impact. Financing schemes tend to focus on the promotion of multiple inter-related energy efficiency improvements leaving property owners the freedom to choose from a set of improvements, which complicates the evaluation. Moreover, a general problem with the evaluation of voluntary programmes is separating the effect of programme participation (i.e. borrowing money to invest in energy efficiency improvements) from the effects of other factors that might make people more likely to participate in the first place. A recommendable way forward to avoid selection bias when evaluating the impact of a financing scheme on energy use is thus to conduct randomized controlled trials (Palmer et al. 2012). A complete analysis of energy efficiency financing schemes would include evaluation of participation rates, loan performance (i.e. delinquency and default rates), and the types of measures that are financed with the loans and, most importantly, estimation of energy savings (ibid.). As regards the evaluation of economic costs and benefits of financing schemes, information requirements beyond the data monitored within the scheme as well as the chosen proceeding depend on the scope of the evaluation, e.g. overall additional investment or employment induced by the financing scheme.

Relevant individual dynamics and side-effects

• Dynamic market transformation and/or innovation: State-run or state aided provision of financing opportunities is an important tool used to generate demand for very energy-efficient building design and renovation concepts (such as Low-Energy Buildings and better Ultra-Low-Energy Buildings, cf. the bigEE Strategic Approach in our Buildings Guide) and energy-efficient technologies, and to promote the development of energy efficiency markets. Eligibility criteria of financing offers that require recipients to invest the granted funds into highly energy-efficient buildings and technologies can lead to an increase in market share of these including cost degression effects, which again reinforce this trend. In Mexico, practically all social housing is now Low-Energy housing due to the Green Mortgage and This-is-Your-Home programmes (cf. the bigEE good practice policy example). In Germany, e.g., about half of new dwellings achieve Low-Energy or Ultra-Low-Energy standards due to the KfW programmes (cf. the bigEE good practice policy example), whereas in some Austrian provinces almost all new buildings are Ultra-Low-Energy buildings today. However, provision of financing alone will not suffice to achieve genuine market transformation, but needs to be supplemented with additional financial, regulatory and informational tools.
• Avoiding lost opportunities: Energy efficiency financing schemes that require recipients, in exchange for funds, to opt for state-of-the-art building design options and BAT can help to avoid lost opportunities in the form of foregone energy savings that result from investments into less efficient technologies with lower upfront cost being made in absence of the financing schemes. If however the conditions for granting funds specify lower energy efficiency requirements than what would be technically feasible and economically reasonable, financing schemes may create lock-in effects at a suboptimal energy efficiency level.
• Minimising rebound effects: Among the different financing schemes, government facilitated third party financing prevents direct and indirect rebound effects at least over the term of the contract, as users employ monetary savings resulting from energy efficiency measures to pay back the investment cost to the implementing entity via the energy bill or property tax. For the other financing instruments, user education on how to use energy-efficient buildings in an energy-efficient way—e.g. in terms of ventilation—may be required to minimise rebound effects.
• Minimising snap-back effects: In order to minimise snap-back effects, public energy efficiency financing schemes should be continued until a genuine market for energy efficiency financing, which is functional without promotional activities of the state has developed. A suitable organisational model to ensure this continuity may be a revolving energy efficiency fund. In addition, once (Ultra-)Low-Energy Buildings have become mainstream in new build and/or renovation with the help of financing programmes they should become the legal standard through the adaptation of Minimum Energy Performance Standards or energy building codes, so as to prevent snap-back effects.
• Minimising free-rider effects: In order to minimise free-rider effects, energy efficiency action that is mandatory due to minimum energy performance standards (MEPS) should be excluded from the pool of actions promoted through the financing scheme for new buildings. The financing should only be offered for significantly higher energy performance levels than legally required. An exception may be the initial phase of first MEPS introduction in developing countries. This rule is also not valid for renovation of existing buildings: here, the energy efficiency improvement is usually required by MEPS only in case a renovation occurs anyway. The high cost of renovation—with or without energy efficiency improvement—may deter investors from implementing it. The financing is therefore also important to trigger renovation at all, including the energy efficiency improvement to levels required by MEPS for the case of renovation. It still is advisable to aim at inducing higher levels of energy-efficient renovation than required by MEPS through steps in the financing and financial incentives, as e.g. the German KfW programmes do (see the bigEE good practice policy example).
• Creating Spill-over effects: In order to maximise spill-over effects of energy efficiency financing schemes, associated economic benefits need to be made transparent and communicated to energy users and private financial institutions alike. Demonstration of the profitability of energy efficiency investments can make the case for a broader incorporation of such practices in standard business portfolios in the private financial sector, which is a precondition for the development of a genuine energy efficiency market.

Design for sustainability aspects
In order to promote sustainability aspects, eligibility criteria for energy efficiency financing offers can be designed to require the use of technologies or material within the implementation of supported measures that fulfil specific sustainability standards with regard to eco friendliness and health compatibility (e.g. the use of recyclable/biodegradable insulation material).

Co-benefits
The availability of advantageous financing opportunities provides energy users with incentives to invest in energy efficiency action, which leads to an increased demand for technologies and services of those working in the building as well as in the financial sector. Accordingly, positive labour market effects can be expected from establishing energy efficiency financing schemes (see the bigEE good practice policy example on the German KfW programmes ).

The following barriers are possible during the implementation of the policy
As with all policies there is a variety of possible implementation barriers. One of the most common barriers that may arise throughout the implementation of energy efficiency financing schemes relates to limited participation through the target group(s). This may be due to a lack of awareness of the scheme’s existence, lack of knowledge on and perceived uncertainty regarding energy efficiency benefits, low attractiveness of financing conditions or cumbersome application procedures.

The following measures can be undertaken to overcome the barriers
In order to address the issue of limited participation the execution of a process evaluation can provide important insights regarding whether and how processes have an impeding effect on uptake within target groups. Based on the results, adjustments to the programme operation can then be made to improve the overall scheme performance. Information campaigns on the existence of financing opportunities as well as the economic benefits of energy efficiency improvements (presenting good practice examples) can help to close the knowledge gap and reduce risk perception among target groups.

The impact of financing schemes may differ widely depending on design options and circumstantial factors. Nonetheless, evaluations of good practice cases show that considerable reductions in energy use are achievable. One example is the extensive financing programme run by the publicly owned bank German Kreditanstalt für Wiederaufbau (KfW), which targets both refurbishment of building stock and new Ultra-Low Energy Buildings. According to a series of evaluation reports, the energy-efficient refurbishment programme saved 2,679, 2,450 and 1,247 GWh/yr of final energy demand in 2009, 2010, and 2011 respectively (BEI & IWU 2010; IWU & BEI 2011; 2012). Moreover, between 2006 and 2010, the energy-efficient construction programme (and its predecessor “Building Environmentally-friendly ”) saved 1,341 GWh/yr as compared to the reference case. In Germany, about half of new dwellings achieve Low-Energy or Ultra-Low-Energy standards due to the KfW programmes (cf. the bigEE good practice policy example), whereas in some Austrian provinces up to 60% of new buildings are Ultra-Low-Energy buildings today (Lebensministerium 2013).
Another example is the mexican Hipoteca Verde (Green Mortgage, GM) scheme, in which almost 500,000 tons of annual CO₂ emissions (0.79 tons per home), almost 400 GWh of electric energy, and almost 500 GWh of LPG have been saved by 630,000 GM homes supported between 2009 and May 2011 (INFONAVIT 2012). In Mexico, practically all social housing is now Low-Energy housing due to the Green Mortgage and This-is-Your-Home programmes (cf. the bigEE good practice policy example).

The costs of implementing financing schemes may differ depending on the type of scheme, its financial endowment and the efficiency of the implementing authority to deliver the funds to the target group(s). In our good practice example of the KfW programmes for energy efficient refurbishment and construction for instance, allocated government funds to provide low-interest loans and (to a smaller part) grants amounted to €4.3 billion between 2009 and 2011 (€2.0 billion in 2009, €1.4 billion in 2010 and €0.9 billion in 2011). Moreover, the provided funds facilitated investments of €16.9 billion to participants of the energy-efficient refurbishment programme over the evaluated period (2009: €8.9 billion, 2010: €5.1 billion, 2011: €2.9 billion) and €7.3 billion to participants of the energy-efficient construction programme over the years 2010 and 2011 (2010: €3.7 billion, 2011: €3.6 billion).
In the example of the Mexican Green Mortgage Programme, the costs corresponded to 900,000 loans extended by October 2012, but no financial figure was disclosed by the implementing agency INFONAVIT. If approximately 50% of the total available Green Mortgage had been spent (value for 2009), total investment for eco-technologies would have been in the range of € 450 million (own estimate).

As with potentially achievable energy savings and expected costs, cost savings and net benefits may differ depending on the properties and implementation effectiveness of financing schemes. Also other factors such as e.g. building costs, expertise of staff in the building sector or user behaviour have an effect on actual outcomes. As an example, evaluations of our good practice example of the KfW programmes for energy efficient refurbishment and construction showed significant cost savings for investors and the government and also labour market related net benefits:

Energy-Efficient Refurbishment:

With regard to heating costs, IWU & BEI (2011; 2012) calculates savings of about €213 million/yr for the 2010 programme year and €125 million/yr for the 2011 programme year. Thus, each of the 181,000 building units refurbished in 2011 saved €690 per year or €60 per month. For an operating life of 30 years of funded energy-efficient measures, heating cost savings from 2011 alone reached €3.3 billion (present value) or €4.2 billion (nominal value) (IWU & BEI 2012, p. 40 et seg.). Energy cost savings (present value) therefore seem lower than the overall investments of €3.85 billion. However, this includes at least 30 to 80 % of costs (depending on energy efficiency action) that investors would have incurred anyway by scheduled refurbishment of walls, windows, roofs, or heating systems without improving energy efficiency. Comparing the energy costs savings only with the incremental investment for energy efficiency improvements will therefore demonstrate a net benefit.
Employment effects from the 2011 programme year add up to about 52,000 person years (92,500 from 2010) of which 38,000 are direct effects (IWU & BEI 2012, p. 42). The loan-option is responsible for 41,000 person years. Overall investments are €3.85 billion, of which €0.6 are VAT or government revenues. A multiplying effect of 1.69 results from additional input processes worth €2.25 billion outside of the construction industry increasing government revenues by about €0.7 billion (IWU & BEI 2012, p. 48).
The energy-efficient refurbishment programme thus results in round about €1.3 billion in additional taxes.

Energy Efficient Construction:

The KfW programme for new buildings is estimated to have saved €35,566,000 of heating costs for 2011, which is €440 for each building unit and €35 each month. For 30 years of operating life IWU calculates total cost savings of €864 million (present value) or €1.1 billion (nominal value).
Employment effects amount to 199,000 person years of which 146,000 person years are direct effects. Overall investments account for €14.5 billion of which €2.3 billion are state revenues (VAT). Thus, the net turnover effect is €12.3 billion. Including input processes, net turnover is €21.5 billion which result in salaries and, again, in government revenues worth €2.7 billion (IWU & BEI 2012, pp. 70-72). The energy-efficient construction programme thus results in total government tax revenues of €5 billion.
However, all of these investment, employment and tax numbers relate to the full cost of construction. The incremental costs of building much more energy-efficiently than required by law are only a few per cent of these, and therefore most likely lower than the energy cost savings.

Both programmes are cost-effective to consumers and even for the government budget. According to IWU & BEI (2012) estimations the new build and refurbishment programmes together result in about €6.3 billion of tax revenues, as compared to €0.9 billion of budget allocation to the programmes. However, this is based on the full cost of construction, not just the incremental costs of energy efficiency improvements.

For the Mexican Green Mortgage Programme, the medium repayment period for homeowners on measures financed under the programme in 2010 was calculated to be 4.1 years. With an assumed medium lifetime of 10 years for all measures (and no maintenance costs considered), the net benefit for the housing owner would be in the range of about €900.