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Biomass-fueled combined heat and power systems (CHPs) can potentially offer environmental benefits compared to conventional separate production technologies. This study presents the first environmental life cycle assessment (LCA) of a novel high-efficiency bio-based power (HBP) technology, which combines biomass gasification with a 199 kW solid oxide fuel cell (SOFC) to produce heat and electricity. The aim is to identify the main sources of environmental impacts and to assess the potential environmental performance compared to benchmark technologies. The use of various biomass fuels and alternative allocation methods were scrutinized. The LCA results reveal that most of the environmental impacts of the energy supplied with the HBP technology are caused by the production of the biomass fuel. This contribution is higher for pelletized than for chipped biomass. Overall, HBP technology shows better environmental performance than heat from natural gas and electricity from the German/European grid. When comparing the HBP technology with the biomass-fueled ORC technology, the former offers significant benefits in terms of particulate matter (about 22 times lower), photochemical ozone formation (11 times lower), acidification (8 times lower) and terrestrial eutrophication (about 26 times lower). The environmental performance was not affected by the allocation parameter (exergy or economic) used. However, the tested substitution approaches showed to be inadequate to model multiple environmental impacts of CHP plants under the investigated context and goal.
Contemporary combined heat and power (CHP) systems are often based on fossil fuels, such as natural gas or heating oil. Thereby, small-scale cogeneration systems are intended to replace or complement traditional heating equipment in residential buildings. In addition to space heating or domestic hot water supply, electricity is generated for the own consumption of the building or to be sold to the electric power grid.
The adaptation of CHP-systems to renewable energy sources, such as solid biomass applications is challenging, because of feedstock composition and heat integration. Nevertheless, in particular smallscale CHP technologies based on biomass gasification and solid oxide fuel cells (SOFCs) offer significant potentials, also regarding important co-benefits, such as security of energy supply as well as emission reductions in terms of greenhouse gases or air pollutants. Besides emission or air quality regulations, the development of CHP technologies for clean on-site small-scale power generation is also strongly incentivised by energy efficiency policies for residential appliances, such as e.g. Ecodesign and Energy Labelling in the European Union (EU). Furthermore, solid residual biomass as renewable local energy source is best suited for decentralised operations such as micro-grids, also to reduce long-haul fuel transports. By this means such distributed energy resource technology can become an essential part of a forward-looking strategy for net zero energy or even smart plus energy buildings.
In this context, this paper presents preliminary impact assessment results and most recent environmental considerations from the EU Horizon 2020 project "FlexiFuel-SOFC" (Grant Agreement no. 641229), which aims at the development of a novel CHP system, consisting of a fuel flexible smallscale fixed-bed updraft gasifier technology, a compact gas cleaning concept and an SOFC for electricity generation. Besides sole system efficiencies, in particular resource and emission aspects of solid fuel combustion and net electricity effects need to be considered. The latter means that vastly less emission intensive gasifier-fuel cell CHP technologies cause significant less fuel related emissions than traditional heating systems, an effect which is further strengthened by avoided emissions from more emission intensive traditional grid electricity generation. As promising result, operation "net" emissions of such on-site generation installations may be virtually zero or even negative. Additionally, this paper scopes central regulatory instruments for small-scale CHP systems in the EU to discuss ways to improve the framework for system deployment.
The South African government started the development of a basic energy efficiency policy framework in 2005, including a voluntary label for refrigerators. This initial label was the intended precursor to a mandatory standards and labelling (S&L) programme, but the impacts achieved were only very limited. Based on this first experience, the South African Bureau of Standards (SABS) formed in 2008 a working group for the development of the new and more specific South African National Standard SANS 941. This standard identifies energy efficiency requirements, labelling and measurement methods as well as the maximum allowable standby power for a set of appliances as reliable basis for introducing a mandatory regulation. Nevertheless, due to many existing barriers, such as lack of funding and low priority assigned to the initiative, a very long period passed by between the S&L planning and final policy implementation. Finally, in November 2014, the South African government published mandatory performance standards coming into force in 2015/2016 for a first set of appliances consisting of refrigerators, washing machines, dryers, dishwashers, electric water heaters, ovens, A/C and heat pumps. To analyse the effectiveness of the new S&L programme and the potential influence of delays in the implementing process, the authors performed an immediate first-hand evaluation of the new policy.
As analytical reference base for available energy efficiency potentials, results from bottom-up scenario calculations will be presented exemplarily as case study for cold appliances covered by the S&L programme. A retrospective market study will show market trends before policy implementation and compare results with the new mandatory requirements. For the further policy analysis, a programme theory approach will be applied, in order to better understand why, how and under what conditions the policy works. Relationships with other energy efficiency policies and measures as well as positive or negative effects will be described. Furthermore, cause-impact relationships will be analysed to explain the functioning of the policy. Finally, success and failure factors will illustrate what needs to be done to achieve the desired energy efficiency targets. Henceforth, even though this study does not assess the direct transferability of the South African S&L programme to other regions, its findings could be relevant and useful for countries planning the implementation of similar policies.
Washing laundry is one of the most widespread housework tasks in the world. Washing machines, performing this task already in many private households, are now responsible for about 2% of the global electricity consumption. Worldwide, more than 840 million domestic washing machines are in use, with an annual consumption exceeding 92 TWh of electricity and 19 billion m3 of water as well as causing emissions of more than 62 megatons CO2eq. In North America, Western Europe and Pacific OECD countries, most households own a washing machine. In these economies standard and label policy programs already addressed and reduced the specific electricity and water consumption of washing machines per wash cycle. Nevertheless, in other world regions, the level of ownership for washing machines is still well below saturation and high growth rates can be observed in developing and newly industrialising countries. As washing machines use water, electricity, chemical substances and process time as resources, also the absolute worldwide resource consumption and emissions of these appliances are still on the rise. Due to different washing habits and practices as well as types of washing machines in different world regions, the specific consumption of resources for doing the laundry is varying to a large extent. On that score, this paper presents an overview of the current situation worldwide as well as respective saving potentials. Bottom-up scenario calculations, carried out for the 11 world regions according to the Intergovernmental Panel on Climate Change classification, show that large energy, water and greenhouse gas savings are possible with the "Best Available Technologies" today, and even higher savings will be possible with next generation "Best Not yet Available Technologies". According to model results, these savings are usually also very cost-effective. Following these calculations, it is highly advisable for policymakers world-wide to pay even more attention to improvement options in order to implement ambitious and product-specific policy packages, including minimum performance standards and labelling schemes.
Small-scale residential biomass combustion for space heating and warm water production already holds a considerable share on overall energy production from biomass in Europe. In the existing regulative framework of EU air quality and climate protection targets, an extended usage of renewable biomass heating without an increase of harmful emissions is urgently needed. In this context, the FP7 project "EU-UltraLowDust" (ULD) aimed at the demonstration of highly efficient and ultra-low emission small-scale biomass combustion technologies and the development of supporting policy recommendations.
New combustion technology operating at almost zero particulate matter (PM) emissions has been demonstrated, rivalling even the performance of state-of-the-art natural gas fuelled systems. In this context, the authors analysed EU policy options for a faster diffusion of these new innovative technologies. The analysis presented in this paper is based on results from an original impact assessment with special focus on energy efficiency and emission scenarios, including the potential effects of a broad deployment of the new ULD technologies as well as the early replacement of poor performing existing installations.
As the derived results show that major shares of energy consumption and emissions from residential biomass combustion in the EU are caused by old heating systems, specific policy measures for new and existing installations have been analysed. Following this, a recommended and harmonized policy package for new Small Combustion Installations (SCI) to be put on the market as well as for existing SCI in the stock has been developed, which will be presented in this paper. The basic policy package addresses new installations and consists of a two-step approach, aiming at enhancing the current and forthcoming policies addressing the SCI market in Europe. A complementary second policy package for existing installations aims specifically at the early replacement of SCI already installed in the stock, which are characterized by low efficiency and high emissions.