Malaysia generated 156,665 gigawatt-hours (GWh) of electricity in 2016 of which the biggest share of 48.4% was sourced from coal and coke. Malaysia coal consumption was met by 90.5% of imported coal due to high demand from the power sector. Malaysia also has a vast biomass resource that is currently under-utilised for electricity generation. This paper reviews the potential of oil palm residues and municipal solid waste (MSW) for alternative coal replacement employing hydrothermal treatment (HTT). In 2017, about 51.19 million tonnes (Mt) of oil palm waste was available with 888.33 peta-joule (PJ) energy potential to generate 88.03 terawatt-hours (TWh) electricity from oil palm fronds (OPF) and oil palm trunks (OPT), empty fruit bunch (EFB), mesocarp fibre (MF), palm kernel shell (PKS) and palm oil mill effluent (POME). Meanwhile, the MSW energy potential and electricity generation potential was estimated at 86.50 PJ/year and 8.57 TWh/year, respectively. HTT with washing co-treatment eliminates the use of drying for converting range of biomass and MSW into clean solid fuel known as hydrochar. The hydrochar increased in caloric value with lower moisture, Potassium (K) and Chlorine (Cl) contents. These value-added fuels can be used as coal alternative and reduce dependency on imported coal for energy security in Malaysia.

High penetration of electric vehicles (EVs) leads to high stress on a power grid, especially when the supply cannot cover and actively respond to the unpredictable demand caused by charging EVs. In the Java-Madura-Bali (JAMALI) area, Indonesia, the capability of the grid to balance its supply and demand is very limited, and massive EV charging additionally worsens the condition because of unbalanced load profiles. Ancillary services of EVs have led to the idea of utilizing EV batteries for grid support, owing to their high-speed response to the fluctuating power system. In this study, a techno-economic analysis of the vehicle-to-grid (V2G) system in the JAMALI grid is conducted in terms of the changes in the feed-in tariff schemes, including regular, natural, and demand response tariffs. The results show that by utilizing EVs, the supply during peak hours can be reduced by up to 2.8% (for coal) and 8.8% (for gas). EVs owned by business entities as operating vehicles with a natural tariff show the highest feasibility for ancillary services, and can potentially reduce the cost of charging by up to 60.15%. From a power company perspective, V2G also potentially improves annual revenue by approximately 3.65%, owing to the replacement of the fuel.

Saudi Arabia has taken major steps to shift from an oil-centered to more environmentally-focused economy. One approach made recently is to enable households to possess and generate electricity by using small-scale residential solar photovoltaic systems (RSPSs). However, the number of applications to install this technology in residences is significantly low. Social acceptance of solar energy is essential for a successful energy transition. Hence, the present study aims to examine factors that may potentially motivate or impede individuals from purchasing RSPSs based on the diffusion of innovations theory. A cross-sectional, web-based survey is conducted including 1498 participants from the five main regions of Saudi Arabia. Results revealed a good cognition level in relation to solar energy, where the majority (64–83%) of respondents are aware of the benefits. An overwhelming proportion of the respondents (97%) associate RSPSs with a significantly positive image, with no significant variation in the acceptance or rejection rates among the five areas covered by the survey (p = 0.1). The results also show high statistical significance for the differences between RSPS acceptors and rejecters in all innovation attributes (p < 0.001). However, the perception of relative advantage has a higher correlation with acceptance RSPSs. These perceived advantages were of rather long-term nonfinancial benefits, such as environmental protection against global warming and provision of unlimited power, rather than the revenue related to direct costs benefits. The study also revealed that the installation cost was the most significant barrier to adopting the RSPS, which can be a focus for RSPS dissemination policies.

Purpose: Despite the long-standing demand for research on dynamic lifecycle assessment (LCA) for policymaking, only a few studies have addressed this subject in conjunction with other systems thinking disciplines, such as energy systems models (ESMs) and integrated assessment models (IAMs), which have achieved tremendous success in assessing climate policies in future scenarios. This study explains our methodological advances in the global application of LCA incorporated in IAMs, specifically dose-response functions, models, and future scenarios. Methods: We investigate the application of the lifecycle impact assessment method based on endpoint modeling (LIME), developed under the current environmental situation in Japan and globally, to be consistent and compatible with our IAM, which comprises three resource balance models and a simplified climate model. The IAM endogenously generates most inventories consistent with energy scenarios and climate policies linked with the applied LIME. The IAM and LIME are formulated to minimize the discounted sum of supplying the cost of resources over their lifecycles (i.e., from development to end-of-life) to generate time evolutions for the endpoint impacts over this century on a global scale with/without the 2-degree Celsius (2DC) target in a 100% renewable energy scenario. Results and discussion: Unlike existing LCA+ESM/IAM studies, which focus on power generation technologies and related (in)direct embedded energy consumption on a lifecycle basis, our model’s expansion to mineral and biomass resources, in addition to energy, has the following novel results: (1) The following inventories in the 2DC target are generally lower than those in business as usual (BAU): temperature and sea level rise, natural resource, and waste discharge; further, SOx emissions are significantly reduced by reducing coal production while increasing forestry. (2) The environmental impacts on the four endpoints of minerals, land use, and land-use change, with the exclusion of energy-related impacts, are significantly larger than those related to energy. (3) Finally, by ensuring inventory reduction, the 2DC target scenario can reduce overall endpoint impacts (by maximum around 20%), except the impacts on biodiversity resulting from forestry expansion to meet predetermined targets. Conclusions: Unlike mainstream IAM analyses, we incorporate LIME, instead of energy- and biomass-related resource and climate change impacts alone; our model thus provides a comprehensive perspective on various natural resources and their impacts on a lifecycle basis. The exclusion of the weighting process and retention of the four endpoints enable us to easily interpret the results. Further, this application of LCA to IAM enables us to further understand and assess natural resources and environmental impacts.

The deployment of highly efficient cooling equipment is expected to promote energy savings and greenhouse gas emissions reductions in the tropics. A ground source heat pump (GSHP) has high energy-savings potential for use in Bangkok, Thailand. This study aimed to elucidate the operational conditions of a GSHP when used in Bangkok which was expected to achieve a higher efficiency than an air source heat pump (ASHP) over the long term. An operational experiment on a pilot facility in Bangkok and a simulation over a three-year GSHP operation were conducted. As a result of the operational experiment and simulation, the proposed operational condition was that the 90th percentile value of the hourly heat pump (HP) inlet temperature did not exceed 5 °C above that of the hourly annual ambient temperature during the third year of operation. When a GSHP designed based on this condition was utilized for a small government building, the required number of boreholes were 24, 4, and 3 for air-conditioned areas of 200, 40, and 25 m², respectively, which achieved 40% energy savings. Thus, a small-scale GSHP in Bangkok designed based on the proposed condition can achieve high efficiency within space limitations.