• Energy Research
• 2016-2025close
• Indonesian close
• University of North Sumatra close

Water is an important part of everyday human life, we usually use water for direct consumption or we use it in household work and other purposes. As one of the largest archipelagic countries in the world which has a coastline of 95,181 km, Indonesia has abundant sources of sea water so that sea water can be utilized in areas that have difficulty accessing clean water directly, especially people living in coastal areas. One of the technologies that can be utilized so that this abundant seawater can be consumed is by conducting a solar distillation process. This study aims to compare the results of clean water productivity and efficiency from a passive distillation system with an active system using an atomizer nozzle. The results showed that in this experimental test there was an increase in the efficiency of the active system with the atomizer compared to only using the passive system, with efficiency values of 47.1% and 38.48%, respectively. ; Air merupakan bagian penting dalam kehidupan manusia sehari-hari, air biasa kita gunakan untuk dikonsumsi secara langsung atau kita gunakan dalam pekerjaan rumah tangga dan keperluan lainnya. Sebagai salah satu Negara kepulauan terbesar di dunia yang memiliki garis pantai sepanjang 95.181 Km, Indonesia memiliki sumber air laut yang melimpah sehingga air laut tersebut dapat dimanfaatkan di daerah yang kesulitan akses air bersih secara langsung khususnya masyarakat yang tinggal di daerah pesisir pantai. Salah satu teknologi yang dapat dimanfaatkan agar air laut yang melimpah ini dapat dikonsumsi adalah dengan melakukan proses penyulingan tenaga surya. Penelitian ini bertujuan untuk membandingkan hasil produktivitas air bersih dan efisiensi dari penyulingan sistem pasif dengan sistem aktif dengan menggunakan nozzle pengabut. Hasil penelitian menunjukkan bahwa pada uji eksperimental ini bahwa terjadi peningkatan efisiensi dari sistem aktif dengan pengabut dibandingkan hanya memakai sistem pasif, dengan nilai efisiensi masing-masing 47,1% dan 38,48%. ; 110 Halaman ; Skripsi ...

Design of solar energy tuners using digital compass and rtc based miktrokontroller Atmega 328 is a tool used to follow the direction of the movement of the sun every hour, ranging from rising to bright. This solar energy tuner will setting the time setting inputted by RTC (Real Time Clock). This tool uses Atmega 328 microcontroller as the data manager of the circuit. The solar panel is driven by a servo motor that moves in the direction of the digital compass and the input time given by the RTC. The movement of solar panels is set with a proven angle, so that the position of the solar panel is always perpendicular to the direction of the coming sun. ; Rancang bangun penala energi matahari memanfaatkan digital kompas dan rtc berbasis miktrokontroller Atmega 328 merupakan sebuah alat yang digunakan untuk mengikuti arah pergerakkan matahari setiap jamnya, mulai dari terbit hingga terbenam. Penala energi matahari ini akan mendeteksi setting waktu yang diinput oleh RTC (Real Time Clock). Alat ini menggunakan mikrokontroller Atmega 328 sebagai pengelola data dari rangkaian. Panel surya digerakkan dengan menggunakan motor servo yang bergerak sesuai arah digital kompas dan input waktu yang diberikan oleh RTC. Pergerakkan panel surya diatur setiap jam dengan sudut yang telah diuji, sehingga posisi panel surya selalu tegak lurus dengan arah datangnya cahaya matahari. ; Skripsi Sarjana

Natural disaster monitoring instruments as an integrated early warning system had been widely developed and placed in areas that were estimated to be prone to natural disasters. This was done to help the government and the public take pre-disaster and post-disaster actions to reduce losses experienced. However, the placement of these monitoring instruments had many shortcomings, one of which was the theft of the main component of the battery or battery which was a power source to activate the instrument. An alternative technology was used to overcome this problem, namely by relying on power transmission with fiber-optic-based laser light. Laser light will be sent to the location using optical fiber which was then emitted to the solar panel so that the laser light was converted into electrical energy. The power generated by solar panels illuminated by 810 nm laser with an input power of 140 mW was 7.76 mW. The power that must be given to an 810 nm laser to produce the same power when solar panels were illuminated by the sun was 12,743 W. So, laser light transmission with fiber optic media as an alternative to providing energy sources in disaster monitoring instruments can be used to reduce losses ; 112 Halaman ; Skripsi Sarjana

Biodiesel merupakan bahan bakar alternatif untuk mesin diesel yang terdiri dari alkil monoester dari minyak tumbuhan atau lemak hewan. Tujuan dari penelitian ini adalah untuk memanfaatkan Waste Cooking Oil (WCO) dalam pembuatan biodiesel dengan menggunakan katalis SiO2 dari tongkol jagung yang diimpregnasi dengan KOH. Tongkol jagung dikalsinasi pada suhu 700oC selama 3 jam, kemudian diimpregnasi dengan KOH dengan rasio molar 2:1. Bahan baku yang dipergunakan dalam penelitian ini adalah hasil treatment dari WCO dengan menggunakan karbon aktif. Dihasilkan Treated Waste Cooking Oil (TWCO) dengan penurunan kadar FFA dari 1,24% menjadi 0,5%. Pada penelitian ini dipergunakan berat katalis 2,3,4, dan 5% serta suhu reaksi 55oC, 60oC, dan 65oC. Adapun Hasil terbaik yang dihasilkan, yield maksimum dari biodiesel adalah 97,87% dengan konversi 99,77% yang diperoleh pada kondisi rasio molar TWCO:metanol yaitu 1:12, berat katalis 3%, Waktu reaksi 3 jam, pengadukan 700oC, dan suhu reaksi 60oC. ; Biodiesel is an alternative biofuel for diesel that consist of alkil monoester .It produces from vegetable oil or animal fats. The purpose of this research is to use Waste Cooking Oil (WCO) for making biodiesel using catalyst SiO2 that produce by impregnation of corn cob and KOH. Corn cob calcinated at 700˚C for 3 hours, then impregnated with KOH at rasio 2:1. WCO that had been treated with activated carbon is used for making this biodiesel. The deacrease of free fatty acid from that Treated Waste Cooking Oil (TWCO) is from 1,24 % to become 0,5 %. The weight of catalyst that is used in this research is 2, 3, 4, and 5% at 55˚C, 60˚C, dan 65˚C. The optimum result for this research to get 97,87% maximum yield, and 99,77% for the convertion is by using molar ratio between TWCO: methanol at 1:12, 3% catalyst at 60˚C in 3 hours. ; Skripsi Sarjana

Perkembangan kebutuhan tenaga listrik terus meningkat. Hal ini meyebabkan perlunya pengembangan pemanfaatkan energi terbarukan. Salah satu sumber energi listrik ramah lingkungan adalah Turbin Angin. Terdapat beberapa metoda untuk meningkatkan efisiensi kerja turbin angin. Pitch Angle Control pada turbin angin (Wind Turbine) telah banyak digunakan untuk mengurangi torsi dan variasi daya keluaran saat kecepatan angin yang tinggi. Namun menggunakan kontrol ini untuk memaksimalkan daya yang terdapat pada energi angin juga merupakan pengaruh yang ditimbulkan dengan menambahkan kontrol pitch angle. Tulisan ini membahas tentang pengaturan pitch angle turbin angin dengan menggunakan Fuzzy Logic Controller (FLC) yang mana kontrol ini mempengaruhi koefisien performansi (Performance Coefficient) pada turbin angin. Penelitian ini menghasilkan dasar pengaturan kontrol yang mampu menghasilkan pembangkitan energi angin di Kota Medan khususnya daerah Tuntungan dan sekitarnya menjadi efektif dengan tetap menjaga keamanan kerja turbin angin. Hasil simulasi menunjukkan bahwa penambahan kendali logika fuzzy pada pengaturan sudut baling-baling turbin mampu meningkatkan efisiensi kerja turbin angin sebesar 11,9% dibandingkan saat menggunakan sudut tetap 10o, dimana sudut tetap sebesar 10o dianggap paling optimal untuk kondisi angin kota Medan. 110402041

The purpose of this study is to analyze conversion of waste into biogas cattle against the income of the people in Karo and Deli Serdang. This study use primary data through questionnaires and interviews to people who are or have been managing the biogas from cattle waster in Karo and Deli Serdang. The analytical methods used in this study are descriptive statistics and multiple linier regression. The resuld showed that the time use of biogas, the price of cow manure and the number of dependents simultaneously positive and significant impact on people’s income. The time use of biogas is partially not significant positive effect on people’s income and the price of cow manure partially not significant positive effect on people’s income and the number of dependents partially positive effect is not significant to people’s income 100501159

Background: Indomethacin is a very effective nonsteroidal antiinflamatory drugs, but it can cause gastric iritation if it is given orally. Therefore, the delivery system of indometachin through skin can avoid local side effect causedin gastric. Purpose : The purpose of this research is to know the effect of ethanol, glycerine and mixture of ethanol and glycerine to the penetration of indomethacin from gel preparations in vitro by using the skin of rabbit and using indometasin gel from Japan (Kowa, Japan) as the comparison. Methods: This study was made 12 gel formula containing indomethacin 1% with alginat gel base include formula F1 without contained enhancer. Formula F2, F3 and F4 with the concentration of ethanol 3, 5 and 7%. Formula F5, F6, F7, and F8 with the concentration of glycerine 45, 50, 55 and 60%. Formula F9, F10, F11, and F12 with the concentration of mixture of ethanol 3% with glycerine 45%, ethanol 5% with glycerine 45%, ethanol 7% and glycerine 45% and ethanol 5% and glycerine 55% and then compared with the indomethacin gel from Japan. Indomethacin penetration in vitro test were done through fur free rabbit skin from the alginate gel base by using diffusion cell. The amount of indomethacin penetrate in phosphate buffer solution pH 7.4 was determined by UV spectrophotometer on 265.0 nm wavelength. The experiments were done for 9 hours. Results: The results showed that the addition of ethanol 5%, glycerine 55% and mixture of ethanol 5% with glycerine 55% increased the penetration of indomethacin. Mixture of ethanol 5% and glycerine 55% provides the highest penetration. The effect of the addition of ethanol, glycerine and mixture of ethanol and glycerine indicate the number of indomethacin which penetrated from the order of the most high to low is mixture of ethanol and glycerine > ethanol > glycerine. Conclusions: From the results of this study concluded that mixture of ethanol and glycerine provides the highest penetration of indomethacin. 111501030

Bioethanol fuel gel is renewable energy (renewable energy) potential as the source is updated and more secure when compared with liquid bioethanol. Besides ethanol gel fuel is also cheaper than fossil fuels such as premium, gas and kerosene. However, the use of bioethanol gel as a substitute for fossil fuels are still very minimal. This is due to factory producing bioethanol gel is limited and little is know how to capitalize on bioethanol gel that can be used in everyday life, as well as bio-ethanol gel stoves. For that, a special study is needed regarding the manufacture and performance of bioethanol gel-fueled stove.This study aims to create a prototype stove bioethanol gel and seek to know the characteristics and comparative performance of bioethanol gel fuel stove by creating a wide variety of combustion (burner) and the air hole diameter 5 mm, 4 mm, 3 mm, 2.5 mm, and 2 mm. Control variables in this study is the production of bioethanol gel CV. Fresh Joy International with ethanol content of 70%, 1.05% Carbopol, 7.33% moisture content with HHV 16942.572 (kJ / kg) and LVH 16717.369 (kJ / kg). Incinerators (burner) made from canned drinks (soft drinks) ex. The data in this study will be processed using a method Boilling Water Tester (WBT) in order to obtain results in the form of influence each - each a variation on bioethanol fuel burner on the stove gel. From the study showed, a stove with a second variation (V2) with a diameter of 4 mm air holes are stoves most effective and efficient with thermal efficiency values (hc) 67% and, blue flame characteristics and stable. 130421008

Deep Eutectic Solvent (DES) dapat dibuat dari campuran a quarternary ammonium salt dan hydrogen bond donour. DES merupakan pelarut yang tidak beracun dan biodegradable dibanding pelarut organik seperti n-heksana serta memiliki harga yang lebih murah dibandingkan Ionic Liquid lainnya. Aplikasi DES sebagai co-solvent pada proses metanolisis biodiesel pada bahan baku degummed palm oil (DPO) dilakukan untuk mengetahui pengaruh jumlah DES yang digunakan. Pada penelitian ini, DES dibuat dari campuran Choline Cloride (ChCl) dan gliserol dengan rasio molar 1:2. Campuran ChCl dan gliserol dipanaskan hingga suhu 80 °C dan sambil dihomogenkan dengan kecepatan pengadukan 300 rpm selama 1 jam. Hasil yield metil ester tertinggi yang diperoleh adalah 85,00 % dengan kemurnian ester 96,23 % dan rasio molar metanol : DPO 6:1, jumlah DES 1,5 %, katalis 1 %, temperatur reaksi 60 °C, dan kecepatan pengadukan 400 rpm. DES sebagai cosolvent dalam metanolisis tidak mampu meningkatkan yield metil ester yang diperoleh dibandingkan dengan hasil yield biodiesel tanpa penambahan DES. 120405048

This study was aimed to discover the effectiveness of tamarind seeds as adsorbent for the reduction of free fatty acid content (FFA) and peroxide value (PV) in CPO (Crude Palm Oil) at the best adsorbent dose and contact time. Materials used were crude palm oil (CPO), tamarind seeds, nitric acid, and distilled water. Variables observed were adsorbent : nitric acid ratio and oven temperature in adsorbent activation process, and contact time and adsorbent dose in adsorption process. This study was began with adsorbent modification, where the cleaned and crushed tamarind seeds to pass through 140 mesh were activated with 4 N nitric acid at 1:1, 1:2, 1:3 and 1:4 of adsorbent : nitric acid ratio while heated at 80 oC for 2 hours. Adsorbent was then dried in oven at 110 oC, 120 oC, 130 oC and 140 oC. Adsorbent with the higher iodine number was used in adsorption of FFA and PV process in CPO that was carried out by heating 100 grams of CPO on hot plate at 90 oC with 1000 rpm of stirring speed, and followed by adsorbent addition of 0.5 %, 1,0 %, and 1,5 % (of CPO used) and 25, 35, and 45 minutes of contact time, and after that oil was filtered using vacuum pump. The study results showed that the best ratio of adsorbent : nitric acid 4 N was 1:2 at 130 oC of oven temperature with 511.773 mg/g of iodine number. The best adsorbent dose was 1.0 % at 35 minutes of contact time that gave higher reduction of FFA with FFA content of 3,923 % and reduction percentage was 20,52 %, and reduction of PV with peroxide value of 0,00868 meq/kg and reduction percentage was 39,72 %. This study showed that adsorbent from tamarind seeds were activated with HNO3 was effective to reduce FFA content and PV in CPO. 00405029