This session will cover electricity as it relates to: (1) manufacturing sector requirements and monetizing the life cycle benefits for increased grid integration, (2) options for Turkey to manage tradeoffs between life cycle environmental, social, and economic sustainability of their electricity mix, and (3) life cycle environmental benefits of batteries and power-to-gas as storage options. Discussion will focus on understanding the important inputs of these LCAs and how the results can be applied.

Key Discussion Points:

  1. What are the most important assumptions/inputs in your LCA?
  2. What are the biggest barriers to achieving optimal results of your LCA?
  3. What kind of support from government/industry would be ideal to achieve the optimal results of your LCA?
  4. How will your results be impacted by a changing grid mix (e.g., increased reliance on natural gas and renewables)?
13:30 Yemane Weldemichael and Getachew Assefa

Life cycle human toxicity and ecotoxicity assessment of bioenergy strategy in decarbonizing Alberta’s electricity grid system

ABSTRACT. Renewable energy generation sources are becoming more diverse as concerns over sustainable development grows. Bioenergy source is promising in addressing Alberta’s sustainable development by increasing electricity generation capacity and mitigating climate change. However, energy systems are complex and may result in shifting of impacts if their effects beyond climate change are not examined. Human toxicity and ecotoxicity is important aspect of environmental sustainability of bioenergy systems that remains largely unstudied (1). About 85% of Alberta’s electricity generation installed capacity is mainly from fossil fuels. Electricity consumption has also been growing at an alarming rate due to population growth and power-intensive economic development. Alberta has a wealth of renewable biomass resource potential that can decarbonize the electricity grid system in terms of GHG emissions. Not all renewable energy strategies are environmentally sustainable. Exposure to air pollution claimed lives of around seven million people worldwide in 2010, largely from biomass combustion for cooking and heating in households (2). This research applied a life cycle assessment approach to examine the human toxicity and ecotoxicity effects of three bioenergy pathways, namely monocombustion of wood biomass, monocombustion of pellets, and biomass integrated gasification and combined cycle (BIGCC) for the case of Alberta. Our preliminary analysis of BIGCC and coal fired at power plant (i.e. excluding raw material extraction and infrastructure) systems showed that bioenergy systems significantly reduce both human toxicity, non-cancer and ecotoxicity impacts. Human toxicity, cancer was a trade-off. The environmental impact per kWh coal-fired electricity generation was 5.34E-12CTUh human toxicity, cancer, 2.85E-13CTUh human toxicity, non-cancer, and 0.000361CTUe ecotoxicity. On the other hand, BIGCC resulted in 1.44E-09CTUh human toxicity, cancer, 6.49E-17CTUh human toxicity, non-cancer, and 2.46E-06CTUe ecotoxicity impacts per kWh. Climate change could not be used as a single indicator to represent the environmental sustainability of a system (3). Quantifying the life cycle toxicity effects of bioenergy systems can support energy strategy and policy making by providing a complete picture of the environmental sustainability of the product. When considering bioenergy as alternative to fossil fuels we must better understand not only climate change impact but also potential impacts on human health and ecosystems.

13:45 Mohammad Abotalib Abotalib and Fu Zhao

LCA Harmonization for Carbon Capture and Sequestration in Coal-fired Power Plants

ABSTRACT. CCS technologies have the potential to become a widely-used option for low-carbon electricity in the power-generation industry in general, and more specifically in the coal-fired power industry. Briefly, CCS collects and compresses CO2 from point sources, including those in the power-generation industry, and then transports CO2 typically by pipeline into deep geological formations. In this paper, the life cycle assessment (LCA) harmonization approach has been applied to the amine-based post-combustion carbon capture and sequestration (CCS) with the aim of reducing the variability observed in the published literature for four environmental impact categories: (1) global warming potential (GWP), (2) acidification potential (AP), (3) eutrophication potential (EP), and (4) cumulative energy demand (CED). The harmonization procedure was applied to the results of 42 published studies representing 57 environmental impact estimates, which were then refined to 44 estimates representing various coal-fired technologies. In both the published and harmonized results, a considerable reduction in GWP was observed for all coal-fired technologies. This reduction was associated with an increase in demand for input materials, which would subsequently increase the indirect air emissions throughout the technology value chain. As a result, an increase in CED was observed for all coal-fired technologies, while the impacts on the AP and EP categories varied from case to case. The LCA harmonization exercise has provided meaningful representative data for analysts and decision makers, and statistical information about the impact categories is presented separately for each coal-fired technology.

14:00 Burcin Atilgan and Adisa Azapagic

Life Cycle Sustainability Assessment of Electricity Options for Turkey

ABSTRACT. Turkey is one of the fastest growing energy markets in the world with a rapidly growing economy and population so that meeting energy demand in a sustainable way is important for the country. Based on previous work investigating the life cycle environmental, economic and social sustainability of electricity generation [1-4], this study evaluates energy technologies for Turkey in order to identify most sustainable options.

The study considers the options currently present in the Turkish electricity mix: lignite, hard coal, natural gas, hydro (large and small reservoir and run-of-river hydropower), onshore wind and geothermal. Each technology is assessed using 20 sustainability indicators, addressing 11 environmental, three economic and six social aspects. LCA, life cycle costing and various social indicators have been used for these purposes.

The results suggest that trade-offs are needed, as each technology is better for some sustainability indicators but worse for others. For example, coal has the highest environmental impacts, except for ozone depletion for which gas is the worst option; gas is the cheapest in terms of capital cost and has the lowest worker injuries and fatalities, but it provides the lowest life cycle employment and has the highest levelised costs. Geothermal is the best option for seven environmental impacts but has the highest capital cost. Large reservoir has the lowest depletion of elements and fossil resources as well as acidification and small reservoir is the best option for the global warming potential but both provide low employment. Being fuel free, renewable options score highly for the energy security indicators. Given these trade-offs, the optimal outcome will depend on stakeholder views of the importance of each sustainability indicator. Therefore multi-criteria decision analysis is needed to determine which technologies are preferable: while the outcome depends on the weightings applied, renewables (particularly hydropower) consistently outperform the fossil fuel options.

As far as the authors are aware, this is the first attempt of a sustainability assessment that has been carried out for Turkey’s electricity sector aiming to inform policy makers and electricity generators on the impacts and hotspots and help plan a more sustainable electricity supply for the future.

References 1. Santoyo-Castelazo, E. and A. Azapagic, Sustainability assessment of energy systems: Integrating environmental, economic and social aspects. Journal of Cleaner Production, 2014. 80(0): p. 119-138. 2. Stamford, L. and A. Azapagic, Life cycle sustainability assessment of electricity options for the UK. International Journal of Energy Research, 2012. 36(14): p. 1263-1290. 3. Gujba, H., Y. Mulugetta, and A. Azapagic, Environmental and economic appraisal of power generation capacity expansion plan in Nigeria. Energy Policy, 2010. 38(10): p. 5636-5652. 4. May, J.R. and D.J. Brennan, Sustainability assessment of Australian electricity generation. Process Safety and Environmental Protection, 2006. 84(2): p. 131-142.

14:15 Christian BauerXiaojin Zhang and Chris Mutel

Life Cycle Assessment of integrated energy storage: methodological challenges and case study results

ABSTRACT. Increasing the share of renewable energy in electricity supply is one of the key measures for mitigating climate change, improving air quality, and reducing dependency on fossil fuels. However, the renewable technologies with the highest worldwide potential – wind turbines and photovoltaic panels – are intermittent electricity generators. Since supply and demand in the power system must be balanced, surplus renewable electricity needs to be curtailed, directly stored, or converted into other energy carriers. Today, a variety of storage technologies with different characteristics and preferred applications exist [1]. However, these technologies have hardly been consistently evaluated from the environmental perspective. Existing LCA studies concerning energy storage often feature methodological shortcomings and lack an appropriate systemic perspective, not taking into account the integration of energy storage in the overall energy system [2, 3, 4]. We discuss methodological challenges in LCA of energy storage and present results from case studies evaluating the environmental benefits and potential drawbacks of a) using batteries in regional electricity supply systems with large photovoltaic capacities and b) converting renewable electricity into hydrogen and synthetic methane using “power-to-gas” technologies. Preliminary results indicate that employing batteries can provide environmental benefits if used in an optimized layout of the electricity system; the environmental performance of hydrogen and synthetic methane from “power-to-gas” technologies crucially depends on the source of electricity used for electrolysis, on the source of CO2 for methane production, and on methodological issues such as allocation procedures and reference technologies used for comparative assessment. We conclude that combining intermittent renewable electricity generation and storage technologies can improve the environmental performance of the overall energy system. However, these storage technologies have to be used in an intelligent way and maximising their environmental benefits requires further research explicitly taking into account systemic, temporal and geographical aspects in LCA.

[1] Luo, X., et al. (2015). “Overview of current development in electrical energy storage technologies and the application potential in power system operation.” Applied Energy 137(2015): 511-536. [2] Sternberg, A. and A. Bardow (2015). “Power-to-What? – Environmental assessment of energy storage systems.” Energy & Environmental Science, 2015, 8, 389-400. [3] Reiter, G. and J. Lindorfer (2015). “Global warming potential of hydrogen and methane production from renewable electricity via power-to-gas technology.” The International Journal of Life Cycle Assessment 20(4): 477-489. [4] von der Assen, N., et al. (2013). “Life-cycle assessment of carbon dioxide capture and utilization: avoiding the pitfalls.” Energy & Environmental Science 6(9): 2721-2734.