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• A pavement piezoelectric (PZT) energy harvester design is proposed. • An electromechanical model of the PZT for low frequencies is introduced. • A methodology for characterizing PZT transducers is clearly described. • The estimated power and voltage from the model matches well with experimental data. • The verified model used in Simulink® provides energy harvesting circuit design tool. Energy harvesting consists of capturing untapped ambient energy of various forms, such as mechanical, thermal or solar, and converting it into electrical energy. A significant unexploited source of mechanical energy is from vehicle movement on roadways. This paper presents the development of a piezoelectric energy harvester (PEH) capable of converting mechanical energy from roadways into electricity and uses an electro-mechanical model for characterizing it. The PEH consists of a stack of piezoelectric (PZT) elements connected in parallel. Its electro-mechanical properties were characterized by subjecting it to dynamic loads with peaks ranging from 1.1 to 11 kN and loading frequencies ranging from 2.5 to 62 Hz. The model constants were estimated by fitting a model to experimental data through an error minimization routine. This model is capable of converting load input (N) to voltage output (V) and vice-versa. Its quality of fit was successfully tested in the laboratory using different load amplitudes and frequencies. For an external resistance of 500 kΩ and sinusoidal loads with peaks of 1.1 and 11 kN applied at 66 Hz, the maximum voltage output of one of the PZT stacks was 95 V and 1190 V and the corresponding root mean square power output was 9 mW and 1400 mW, respectively. This model provides the background for the development of a self-powered axle load sensing system for roadway vehicles. [ABSTRACT FROM AUTHOR]

• Detailed energy cost structures are integrated into a recursive dynamic CGE model. • Investment support and electricity import price changes are considered. • Consistent Lithuanian energy development scenarios are analysed. • Domestic electricity does not necessarily provide the net economic benefits. • The advantages of international cooperation are highlighted. The development of domestic energy generation is often expected to provide benefits to the economy through, for example, improved energy trade balance and jobs created. However, the economic impacts of energy development scenarios are not limited to the energy sector, and the decision makers must consider the impacts on the entire economy. In this paper, we analyse the full impacts of increased domestic electricity generation in a computable general equilibrium (CGE) framework. Realistic energy development scenarios are modelled using the MESSAGE energy system model and considered to be exogenously described energy pathways that generate responses from the remaining economy. These technically and economically consistent energy scenarios are incorporated into the computable general equilibrium model through the creation of fixed, variable, and investment cost structures for the energy forms considered. Model application in Lithuanian case revealed the interchangeable character of electricity imports and local generation based on a relatively significant share of imported resources. Depending on electricity market conditions, scenarios with higher domestic electricity generation levels might fail to provide substantial economic benefits: although increasing electricity import prices would create preconditions to increase domestic electricity production and turn Lithuania to the net electricity exporter, gross domestic product (GDP) might decrease due to the negative impacts on other economic activities. International cooperation for least-cost clean energy supply might be economically beneficial to energy importing countries and increasing domestic electricity generation should not be set as the ultimate goal. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the current status of biofuel development and estimates the potential of un-used land for biofuel development. The potential of crops including cassava, sweet potato, sweet sorghum, sugarcane, sugar beet and Jerusalem artichoke were assessed and discussed for different regions considering the geographical conditions and features of agricultural production. If reserved land resources are explored together with substitute planting implemented and unit area yield improved, potential production of ethanol fuel will be 22millionton in 2020. The study also recommends the use of winter idle lands for rapeseed plantation for biofuel production. The potential for production of biodiesel by rapeseed and cottonseed can reach to 3.59millionton. [Copyright &y& Elsevier]

Abstract: Similar to many other countries, all nations in the Greater Mekong Subregion (GMS) have planned or are planning to develop strong national biofuel programs. The overall goal of this paper is to better understand the impacts of global and regional biofuels on agriculture and the rest of the economy, with a specific focus on the GMS. Based on a modified multi-country, multi-sector computable general equilibrium model, this study reveals that global biofuel development will significantly increase agricultural prices and production and change trade in agricultural commodities in the GMS and the rest of world. While biofuel in the GMS will have little impacts on global prices, it will have significant effects on domestic agricultural production, land use, trade, and food security. The results also show that the extent of impacts from biofuel is highly dependent on international oil prices and the degree of substitution between biofuel and gasoline. The findings of this study have important policy implications for the GMS countries and the rest of world. [Copyright &y& Elsevier]

Abstract: Asia’s largest biofuels producers are currently Indonesia, Malaysia, the Philippines, Thailand, China and India. This paper first examines the current status of biofuels in these countries, including the national development targets, strategies, incentives and policies. It then identifies the fundamental driving forces behind the development and promotion of these industries and considers their economic, social and environmental impacts. [Copyright &y& Elsevier]