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Global warming is causing an increase in temperature of the earth's atmosphere, climate change, resulting in the dry season and rising temperatures. Efforts to control global warming is with the plant the absorption of carbon. One of which is rubber plant that has a high potential carbon reserve. The purposed of this researched was to know the carbon content in each section rubber tree (Hevea brasiliensis Muell. Arg.) and determined the potential of carbon reserved in the rubber tree (Hevea brasiliensis Muell. Arg.) Age of 5 years in people plantation Serdang Bedagai. The method of estimaty carbon stocks done destructive and selection of plant samples carried out with purposived sampling. The carbon content in each section rubber trees (Hevea brasiliensis Muell. Arg.) 5 years of age is different is stem 50.37%, 40.58% branches and leaves 21.68%. The results showed that allometric models for biomass and carbon has W = 0,540 H1.882 and C = 0.053 H 2.526 . The potential of biomass and carbon in smallholder rubber plantations Tarean Village, District Silindak, Serdang Bedagai well 2.71 tons / ha and 1.18 tons / ha. 111201127

Bioethanol is one type of biofuel that developed significantly. The utilization of bioethanol is not only limited for fuel, but also could be used as material for various industries such as pharmaceuticals, cosmetics, and food. With wide utilization and relatively simple production technology has made bioethanol as the most favored biofuel currently. The use of lignocellulosic biomass, microalgae, seaweeds, even GMO (Genetically modified organisms) as substrates for bioethanol production has been widely tested. Differences in the materials eventually led to change in the production technology used. Pretreatment technology in the bioethanol production using lignocellulosic currently experiencing rapid development. It is a key process and crucial for the whole next steps. Based on the advantages and disadvantages from all methods, steam explotion and liquid hot water methods are the most promising pretreatment technology available.

Nowadays the use of cooling engine with refrigerant as its cooling source used by most people, but the use of these refrigerants such as CFCs and HFCs can cause thinning of the ozone layer in the atmosphere and also cause the greenhouse effect. Thermoelectric coolers can be used as a main source of alternative coolers that people needed. One example is the use of cooling box. The purpose of this study was to examine and analyze the cooling load in the cooling box that uses thermoelectric with energy came from photovoltaic. The study was done by using an experimental method in which the cooling box that has been designed, tested to determine the temperature inside the box by using a thermocouple. Other parameters such as Relative Humidity, Intensity of solar radiation, Dew-point Temperature were measured using HOBO data logger. Parameters that have been obtained then processed and calculated using mathematical equations to obtain the cooling load inside the cooling box. This study focused on the calculation of the efficiency of the photovoltaic, the calculation of the coefficient of performance of thermoelectric, the calculation of the capacity of battery to store energy, and analyze the cooling load. The analysis showed that the average cooling load in the cooling box with five 240 ml mineral water is 126,94 Watt, efficiency of photovoltaic is 15,57%, coefficient of performance of thermoelectric is 0,754 and the coefficient of performance of the system in cooling box is 0,225 100401033

Bioethanol is one kind of renewable energy which is being improved in the world to fulfill the demands of energy consumption. Bioethanol which was produced in this research used the hydrolysate of husk cacao waste. The husk cacao is solid waste plantation which is abundant and hasn’t yet had an amount of usings. The purpose of this research is knowing the effect of the quantities of bread yeast used in this research to the length of days fermentation and producing bioethanol got from the hydrolysate of husk cacao waste by using fermentation process added with tannin as preventive oxidation in bioethanol such as formation of acetate acid, and using bread yeast as the source of microorganism to convert into bioethanol. The main substances are the hydrolysate of husk cacao waste produced from acid hydrolysis process using sulphate acid 4 M during two hours at 100 oC degree, tannin, and bread yeast. Afterwards the hydrolysate was fermented in variation sums of bread yeast 3%, 5%, and 7% (w/w) and added with gambier as tannin source in 2, 3, 4, and 5 days and then the hydrolysate was distilled at 80 oC degree by using rotary evaporator having trade mark Ruchi Evaporator R-205. The result of this research indicated that the fermentation process produced bioethanol. The quantitative analysis used GC instrument and the largest content degree of bioethanol was 99,8174% in amount of bread yeast 3% (w/w) in the third day of fermentation and the largest yield degree of bioethanol was 34,4483% in amount of bread yeast 5% (w/w) in the fifth day of fermentation. The qualitative analysis used refractometre having trade mark ABBE to examine refractive index by choosing the sample having the largest content degree of bioethanol and the result was 1,3285 100405045

Common problems facing the world at the present time is the depletion of petroleum reserves and negative impacts of the use of fuel oil. This phenomenon prompted us to look for alternative fuels that can solve both problems at the top, in this case the gas fuel is biogas. This study aims to analyze the performance of the diesel engine designed R175AN TIGER system uses two fuel (dual fuel) diesel and biogas results of palm oil waste to methane content of 70% to produce electricity as well as the addition of catalytic converters in the hope of reducing exhaust emissions. Maximum power is obtained on the use of pure diesel + 4 l / min for 1381.76 biogas Watt, maximum torque occurs in pure diesel + 4 l / min biogas, amounting to 8.8 Nm at 1500 Watt load rotation 1500 rpm, maximum SFC occur on materials diesel fuel loading 600 Watt 1000 rpm rotation of 875.29 g / kWjam, AFR value at solar maximum + 6 l / min biogas load 600 Watt 292.37 rotation of 1000 rpm, the maximum thermal efficiency in solar + 6 l / min for biogas 45.26% at 1000rpm rotation load of 600 Watt, the average effective pressure occurs at solar maximum of + 4 l / min biogas loading 1200 Watt 1500 rpm rotation of 312.93 kPa, the largest opacity on the use of diesel + 2 l / min biogas in 1500 watt load 1500 rpm rotation by 31%. Levels of HC (Hydro Carbon) and CO (Carbon Monoxide) decreased when using catalytic converters. By using biogas can save the economic value of solar 100401108

Due to the decreasing of fosil fuel resources which encourage us to do the research and development of alternative fuels. One of the alternative fuels resources is using sesame seeds (Sesamum Indicum L) to produce biodiesel. This study aims is to analyze the performance of TD - 115 diesel engine using sesame seeds biodiesel mixture of 5 % , 10 % , 15 % and 20 % . The test results indicate that Calorific Value (CV), engine rotations (rpm) and Load (W) given affects the amount of Torque (T) and so the Power (P) decrease up to 36,44 %, while Specific Fuel Consumption (SFC) of the mixture increase up to 148 %, Volumetric Efficiency ( ) decrease up to 16,52 %, Thermal Actual Brake Efficiency ( decrease up to 56,74 % and Heat Losses decrease up to 35,01 %. 110401061

Medan city is located in IMT-GT (Indonesia-Malaysia-Thailand Growth Triangle ) strategic position and included as one of the National Strategic Area. This situation motivates Medan city to be improved into an ideal city. Through the cooperation of Mebidangro (Medan-Binjai-Deli Serdang-Karo), it is expected to create more ideal city and generalize population distribution. By creating ‘magnet’ on the subburbs is a method to attract people to move to new areas. Green Deli Oasis become the ‘magnet’ in north of Medan,and is a renewal of Pulo Brayan cultural areas. GDO Expo and Convention Center is one of the buildings in that area, the building is aimed to be a generator public activities in terms of meetings, conventions, exhibitions and other activities that are visited by many people at one time in the same place. The excessive energy usage is one of global warming causes, thus the energy efficient architecture theme is chosen as the design theme to work out this issue.. Methods which are done in this design process of GDO Expo and Convention Center are literature studies to get an explanation of the design as well as reference / comparisons in the design and field studies to collect necessary physical data. In addition to these studies, interviews and discussions with designrelated- person are also conducted. GDO Expo and Convention Center can be visited 4,000 to 8,000 people for a historical tour activity. Energy efficient architecture theme can applied to the building by utilizing the sun as sources of natural lighting and a solar power, the wind as a natural air conditioning to reduce the usege of air conditioning tools, and rainwater as building water supply. As a result,the building is fungtional, has an attractive visual and can saves energy by utilizing the climates. 120406023

Ditch mud was identical dirtily that is smelly him that was rotten and stang as well as the number of germs penyakit.Solusi best for the problem of ditch mud was by making use of technology biogas.Biogas was alternative energy produced by fermentation of the organic waste that produced gas metan.Penelitian this was the utilisation of technology biogas that have material ditch mud was increased by the waste mixture of cattle and straw padi.Parameter that was observed being the gas pressure (the Atm), time produced gas (the day), old the flame (the second), the ratio of C/N the end. The results showed that the time started producing gas on day 9 and the highest pressures generated in the A2 in the number 0.00205 Psi and the lowest pressure of the gas produced in the A3 in the number 0.000186 Psi, producing an old flame who is found in highest A2 is 30 seconds and the lowest is in the A3 is 24 seconds, the ratio C / N is highest in the A3 for 12.89 and lowest at 6:56 in the amount of A1. 040308015

Biodiesel is an alternative fuel for diesel engines consisting of the alkyl monoesters from vegetable oils or animal fats. Beef tallow is the non-edible raw material with low cost production and the availability is huge in the cattle production. The objective of the study was to utilize waste animal fat (beef) for biodiesel production using solid oxide catalyst. The solid oxide catalyst derived from the industrial waste eggshells. The waste materials calcined with temperature 900oC and time 2 hours, transformed calcium species in the shells into active CaO catalysts. The oil contained high free fatty acid (FFA) content of 1.86%. The FFA content of the oil was reduced by acid-catalyzed esterification. The product from this stage was subjected to transesterification to produce biodiesel. Transesterification process produces methyl ester and glycerol. The produced methyl ester on the upper layer was separated from the glycerol and then washed. Effect of various process variables such as amount of catalyst and temperature were investigated. The biodiesel properties like methyl ester content, density, viscosity, and flash point was evaluated and was found to compare well with Indonesian Standard (SNI). Under the best condition, the maximum yield of 82.43% beef tallow methyl ester was obtained by using 9:1 molar ratio of methanol to beef tallow oil at 55oC, for a reaction time 1.5 hours in the presence 3 wt% of CaO catalyst. The results of this work showed that the use of beef tallow is very suitable as low cost feedstock for biodiesel production. 100405051

Biogas merupakan sumber daya energi berupa gas alami yang dihasilkan melalui tumpukan sampah organik. Biogas diberikan secara gratis kepada masyarakat yang dengan rata-rata tingkat ekonomi menengah kebawah untuk memenuhi kebutuhannya.penelitian ini mengangkat tentang survei kepuasaan masyarakat terhadap penggunaan biogas sampah. Tujuan dari penelitian ini adalah untuk mengetahui kepuasan masyarakat terhadap penggunaan biogas sampah di Gampong Jawa Kecamatan Kutaraja Kota Banda Aceh. Populasi dalam penelitian ini adalah 210 rumah tangga penerima biogas dan dari jumlah populasi tersebut ditetapkan 21 orang sampel pada setiap rumah tangga tangga penerima biogas. Teknik pengumpulan data dalam penelitian ini menggunakan teknik angket dan observasi. Teknik pengolahan data menggunakan teknik deskriptif dan rumus statistik sederhana. Berdasarkan hasil angket menunjukkan persentase jawaban sangat tidak puas sebesar 4,11%, tidak puas sebesar 12,81%, cukup puas sebesar 45,65%, puas sebesar 32,51%, dan sangat puas sebesar 4,92%. Sehingga dapat disimpulkan bahwa pada umumnya masyarakat puas terhadap penggunaan biogas sampah di Gampong Jawa Kecamatan Kutaraja Kota Banda Aceh. Biogas is an energy resource in the form of natural gas produced through piles of organic waste. Biogas is given free of charge to people with an average middle to lower economic level to meet their needs. This study focuses on a survey of community satisfaction with the use of biogas waste. The purpose of this study was to determine community satisfaction with the use of biogas waste in Gampong Jawa, Kutaraja District, Banda Aceh City. The population in this study were 210 biogas recipient households and from the total population, 21 samples were assigned to each biogas receiving household. Data collection techniques in this study using questionnaires and observation techniques. Data processing techniques using descriptive techniques and simple statistical formulas. Based on the results of the questionnaire, the percentage of answers very dissatisfied was 4.11%, dissatisfied at 12.81%, quite satisfied at 45.65%, satisfied at 32.51%, and very satisfied at 4.92%. So it can be concluded that in general the community is satisfied with the use of biogas waste in Gampong Jawa, Kutaraja District, Banda Aceh City