The proposal for the new regulation on climate declarations in Finland requires that all life cycle modules A, B, and C be considered in calculating the carbon footprint. It also requires calculating the so-called carbon handprint (i.e., nearly the same benefits beyond the life cycle [module D]). Climate declaration is naturally calculated using the GWP indicator. However, considering decarbonisation also causes some problems in this context; thus, energy and material resources could be reasonable additional indicators.
The assessment of climate impacts aims to support a low-carbon future. Naturally, the rules of assessment should also support this goal. The life cycle methodology ensures the consideration of all phases while the focus needs to be on today’s emissions because of the urgency of the climate measures.
The methodology for assessing sustainable buildings should reflect reality correctly and support decision-making toward low-carbon choices. The consideration of decarbonisation of energy probably describes the future well. However, this approach provides less support to efforts toward zero-energy building. The consideration of decarbonisation in the manufacturing industry would probably describe the future well but would correspondingly create less pressure for the industry to hasten the implementation of solutions for the low-carbon industry.
Because of this dilemma, the suitability of the GWP (fossil) indicator to describe potential benefits is questionable. Being able to assess and consider the future benefits and problems of different selections is important; however, it is unreasonable to make these comparisons using an indicator that deals with emissions that should be almost zero 50 years from now. Although the current measures – including limit values for buildings’ emissions – will hopefully end GWP (fossil) emissions, there will quite probably be a shortage of available material and energy resources.
Although GWP (fossil) is currently the key indicator, the role and significance of other key indicators should be considered. The importance of indicators that describe the use of material and energy resources, GWP(luluc), and GWP(biogenic) need to be discussed and emphasised.
As a conclusion of the discussion, indicators that describe the consumption of energy and materials resources are important. As the idea of the energy indicator would especially be to reflect the magnitude of the demand for energy, the division for non-renewable and renewable would not be important, although low-energy consumption as such would be. However, regarding materials, considering material types and the origin of materials would be more important.
Embodied and operational GWP and energy indicators
The CO2data database considers all modules, including the D module (benefits beyond the life cycle), and the climate database from Boverket focuses on the A module.
From the life cycle perspective, considering all phases would naturally be recommended. However, considering the GWP impact that will occur several years or 50 years from now is complicated because of the foreseen decarbonisation of energy services and manufacturing processes. This significantly influences operational impacts, end-of-life impacts, and benefits beyond the life cycle. The lack of good-quality data, especially for modules C and D, emphasises the significance of the A module.
The climate database from Boverket provides the GWP values for Swedish electricity and for fuels. The foreseen decarbonisation of electricity is not considered, but the GWP is since these figures are only used for energy use at construction site A5 and shall not be compared with the figure design to be used in B6.
The CO2data defines GWP-fossil values for 100 years for district heating and electricity, considering the decarbonisation calculated based on the foreseen changes because of existing regulations and policies. Both approaches enable the consideration of embodied and operational emissions over a selected period, but the calculation results differ significantly. The Finnish approach probably gives a more realistic picture of the life-cycle impacts. It emphasises the role of product selections and low-carbon product development, while it does not specifically emphasise the meaning of energy efficiency. However, even based on this approach, the energy choices still significantly affect the design’s carbon footprint. Based on the results of a recent interview with building and construction practitioners, energy-related choices are still the focus when searching for possibilities for low-carbon building; however, interest in low-carbon concrete solutions has greatly increased.
From the viewpoint of a carbon-neutral society, the rapid development of low-carbon manufacturing processes and the true decarbonisation of energy services are important. The focus of the proposal for the recast energy performance-building directive is the reduction of operational greenhouse gas emissions. Still, steps are taken to address carbon emissions over a building’s whole life cycle (see Section X). The European standard EN 15978 (2011) does not define specific rules for considering the decarbonisation of energy services. However, Section 8.3.3 says, “Other specific requirements may have to be considered in the description of the life cycle of the object of assessment”. Examples given include regulations and the client’s requirements. When the decrease of the GHG emissions of electricity and district heat are based on the nationally agreed policies and regulations, these may be considered part of other specific requirements.
The following table suggests the pros and cons of the various choices to simultaneously regulate embodied emissions and operational energy or emissions.