In this study, we developed the linear optimization model considering the locations of oil palm mills, the transportation cost of oil palm residue and scale economy of plant. Using the model, we calculated the optimal locations of plants and the product of energy in Malaysia. We obtained the following results. (1) When we assumed the power generation as energy utilization, the scale of power generation plant is 653MW in total. (2) When we assumed the ethanol production as energy utilization, the amount of ethanol is 2434Ml in total. (3) If the power selling price is 6JPY/kWh and the ethanol price is 30JPY/l, only ethanol plants are constructed. (4) If the power selling price is 10JPY/kWh and the ethanol price is 30JPY/l, both power generation plants and ethanol plants are constructed. (5) Type of plant depends on the amount of empty fruit bunch used. (6) Energy utilization using oil palm residue reduces CO₂ emissions.

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Small-Scale biomass power plant with Stirling engine (STE) was developed in this R&D. In wood powder combustion test, air ratio could be down to 1.1 without increasing CO and unburned carbon. Combustion efficiency was higher than 99.9% at air ratio of 1.1. NOx emission was 100 ppm (6%O₂) at air ratio of 1.1, and 200 ppm (6%O₂) at air ratio of 2.5. As results of start-up and shut-down tests, operating performance and safety were quite excellent. It looks easy to establish a full-automatic control and operation system. Ash fouling problem in the heater head of STE was clearly found during wood powder burning. As a result, higher dust loading, higher combustion temperature, and also higher STE inlet gas temperature result larger amount of ash deposit. That is, potassium in wood fuel evaporates in burner zone, and it is accumulated at the surfaces of STE heater tubes. Ca, Si and another ash components are accumulated with together at this moment at the tube surfaces. At the final stage, continuous operation of about 7 hours with cyclone collector was carried out reducing ash fouling. We calculated energy balance, power generation efficiency is 20% in case that preheating air temperature is 600℃.

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In predicting area, size, and timing of the oil and gas field discoveries, it is essential to accurately estimate the ultimate size distribution of oil and gas fields. The size distribution of oil and gas fields is generally considered to be either “lognormal” or “fractal”. However, these analyses do not necessarily estimate the geologically ultimate size distribution of the fields, because the former underestimates truncated small size fields and the latter tends to overestimate those.
Based on the examination of these previous studies, we propose a methodology to estimate the geological size distribution of oil and gas field incorporating the discovery functions of each size segment. The size distribution in a basin is estimated using holomorphic beta function by accumulating each discovery transition function according to the field’s size including truncated or ignored small ones in previous analyses. As a result, the intrinsic size distributions of oil and gas field in regions of our study are estimated as a long tail distribution with a peak in the smaller-scale oil and gas fields than corresponding lognormal distribution. The total ultimate recoverable reserves calculated based on the estimated distributions are between the ones obtained from lognormal distribution and from fractal distribution.

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In this paper, we estimate the wood biomass energy amount stored in the research field and the employment creation through the utilization of wood biomass energy. The research field is a traditional rural area, Yumoto District, in Fukushima Prefecture. The wood biomass energy that is 0-250m distant from the private woodland path in Yumoto District is enough for room heating and hot water demand of all the present households. The periodic utilization of those woodlands in 40 years sustains the wood biomass energy supply system. The energy supply system periodically utilizing 0-100m distant from the private woodland path will reduce 15% of and absorb 10% of the present CO₂ emission per year in Yumoto District. We also find the social background and geographic conditions in Yumoto District are suitable to utilize the wood biomass energy. Some inhabitants still have the forestry techniques. In case of the season employment for 4 months, the wood biomass production business in Yumoto District can create the employments for 5-7 people. Young inhabitants could learn the forestry techniques through this business. There are possibilities that inhabitants manage the national forest and supply wood biomass energy to other districts in the future.

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