No abstract

Depleting fossil fuel sources and worsening global warming are two of the most serious world problems. Many renewable energy technologies are continuously being developed to overcome these challenges. Among these technologies, high-concentration photovoltaics (HCPV) is a promising technology that reduces the use of expensive photovoltaic materials to achieve highly efficient energy conversion. This reduction process is achieved by adopting concentrating and tracking technologies. This study intends to understand and assess the carbon footprint and energy payback time (EPBT) of HCPV modules during their entire life cycles. The social benefit of carbon reduction is also evaluated as another indicator to assess the energy alternatives. An HCPV module and a tracker from the Institute of Nuclear Energy Research (INER) were applied, and SimaPro 8.0.2 was used for the assessment. The functional unit used in this study was 1 kWh, which is produced by HCPV, and inventory data was sourced from Ecoinvent 3.0 and the Taiwan carbon footprint calculation database. The carbon footprint, EPBT, and social benefit of carbon reduction were evaluated as 107.69 g CO 2 eq/kWh, 2.61 years, and 0.022 USD/kWh, respectively. Direct normal irradiation (DNI), life expectancy, and the degradation rate of HCPV system were subjected to sensitivity analysis. Results show that the influence of lifetime assumption under a low DNI value is greater than those under high DNI values. Degradation rate is also another important factor when assessing the carbon footprint of HCPV under a low DNI value and a long lifetime assumption. The findings of this study can provide several insights for the development of the Taiwanese solar industry.

Climate change is an important global environmental threat. Agriculture aggravates climate change by increasing greenhouse gas (GHG) emissions, and in response, climate change reduces agricultural productivity. Consequently, the modern agricultural development mode has progressively transformed into a kind of sustainable development mode. This study aimed to determine the environmental impact and carbon footprint of Dongshan tea from Yilan County. Environmental impact was assessed with use of SimaPro version 8.0.2 and IMPACT2002+. Results showed that climate change has the largest impact upon it in general, followed by human health, natural resources, and ecosystem quality. Furthermore, with use of the IPCC 2007 100a method for carbon footprint of products (CFP), conventional tea was found to have a CFP of 7.035 kgCO2-e, and its main contributors are the raw material (35.15%) and consumer use (45.58%) phases. From this case study, we found that the hotspots of the life cycle of environmental impact of Taiwanese tea mainly come from fertilizer input during the raw material phase, electricity use during manufacturing, and electricity use during water boiling in the consumer use phase (which contributes the largest impact). We propose the ways for consumers to use of highly efficient boiling water facilities and heating preservation, and the government must market the use of organic fertilizers in the national policy subsidies, and farmers have to prudent use of fertilizers and promote the use of local raw fertilizers, and engagement in direct sales for reducing the environmental impacts and costs of agricultural products and thus advancing sustainable agriculture development.

No abstract

No abstract