Guidelines to assess the co-benefits of Plus Energy Buildings

This report summarizes the processes and results of an activity estimating the co- benefits associated with Plus Energy Buildings (PEBs) at household and community
level and aims to provide guidelines to any interested parties who wish to carry out a similar activity in the future. These guidelines can be used by a variety of different
stakeholders, such as real estate agents, building occupants, policy makers and technology developers to estimate and integrate the co-benefits associated with PEBs
into business models and cost assessments, and can be presented within marketing strategies aimed at promoting the use and share of PEBs in the future. Moreover, the
guidelines and estimation of co-benefits aim to demonstrate the importance of the additional benefits for both households and wider society that can originate from PEBs.
This will highlight to policy makers the importance of supporting PEBs with adequate policies, so as to increase their future share, to move past the current norm of the nearly Zero Energy Buildings (nZEB)and to harness the potential gains.
The Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) describes co-benefits as “the positive effects that a policy or measure aimed at
one objective might have on other objectives, without yet evaluating the net effect on overall social welfare” (AR5, 2014). In other words, co-benefits can be thought of as the additional positive effects brought by a policy measure, that occur regardless of and in addition to the originally predetermined policy goals. In the context of PEBs, these can be considered as any additional benefits over and above the energy savings, and therefore, as here called, non-energy co-benefits.
The co-benefits potentially originated by PEBs can be usually attributed to a “use”. Accordingly, they can be evaluated by quantifying a “use value”. This, however, can
encompass both material and immaterial aspects. The first, can be, for instance, a lower quantity of pollutants in the atmosphere, the second, is the sense of satisfaction
originating by living in a more “environmental-friendly” house. In both cases, observable market transactions and official “prices” that can provide support to evaluation may not always be evident. Accounting for these complexities, the present study proposes two different assessment methods: a direct costing approach and a stated preferences approach.
With the first method, we associate, when possible, a straight monetary value to a clearly quantifiable source (i.e. a performance indicator) of co-benefits. With the second
method, we elicit through interviews the preferences, expressed as monetary value assessments of the co-aa clear benefits in a hypothetical setting, of a representative sample of potential users. By asking directly to people, this method allows an evaluation of co-benefits also when “markets” and “prices” are not available.
The co-benefits eventually selected for the direct costing evaluation are the following: At the household level: Reduction of construction material and demolition waste and
lower operational and maintenance costs.
At the community level: Mitigation of climate change, employment creation, improvement in social welfare (reduction in energy poverty), reduction in air pollution
(reduction in emissions of particulate matter), reduced ozone depletion and tropospheric ozone photochemical oxidants, reduction in acidification potential, reduction in eutrophication potential, reduction in abiotic depletion potential for fossil and non-fossil resources and reduced water use.
The two approaches will cover two complementary sets of co-benefits. Direct costing can cover only the co-benefits for which a clear “price tag” can be identified in the
market. For the more immaterial co-benefits, we apply a for the stated preferences evaluation approach to the following final selection:
• Energy Balance: and the role of energy in the building, with a special focus on energy security,
• Indoor Environmental Quality: the (highly subjective) perception of thermal comfort, and air quality,
• Adaptability: the ability of the building to adapt to user needs
In our stated preference study, we explore how much homeowners value co-benefits of energy efficient and positive-energy dwellings, (particularly the co-benefits enhancing energy security), and we test whether investment in them can be made more attractive by boasting about the fact that it will raise the value of the property or its rental income potential. Besides energy security we also explore other co-benefits of energy efficient and positive-energy dwellings among those selected within Cultural-E, namely the improvement in air quality associated with filtration and mechanical ventilation systems typical of zero-energy or positive-energy homes, and the potential of energy optimization systems based on sensors and software dedicated to the electric appliances in the home and to space heating and cooling.
We found that for the most part, respondents were willing and able to answer the rental value questions, even though about one third of the respondents said that the change in rental value was zero for each of the seven hypothetical scenarios they faced. When these “always zero” respondents are excluded, the remainder values connection to a positive energy district some €39/month, centralized air filtration and centralized ventilation about €41/month each, and energy optimization sensors and software €51 (for appliances) and €38 (for space heating and cooling).
The respondents’ valuations appear to be internally valid, in that additional questions about participation in a Positive Energy District (PED) reveal a mean WTP and a mean
WTA for PED participation that bracket the effect of a PED connection on rental values.