Judul: Kajian Manajemen Teknologi Konversi Gas Metana dari Limbah Cair Pabrik Kelapa Sawit Menjadi Energi Listrik
Abstrak: Palm oil mill effluent (POME) emits big amount of methane gas which has potency to be converted to electricity, but it has not been developed at palm oil mills in Lampung. The objectives of this study were to assess some methane capture technologies and the conversion of methane to electricity in order to obtain a recommendation of proper handling for POME in Lampung province. The assessment was done through analysis in technical, environmental, and financial aspects, using data from literatures and interview with managers of PT KIS Indonesia, PT AES AgriVerde Indonesia, and PT Karya Mas Energi. Technology of PT KIS Indonesia with its CSTR reactor is eminent in the type of anaerobic bioreactor, processing time and temperature, generated electricity, and green house gas reduction parameters. On the other hand, technology of PT AES AgriVerde Indonesia and PT Karya Mas Energi with their cover lagoon reactorsare eminent in scale, equipment complexity, and demand for land parameters. Technology of PT Karya Mas Energi is also better in funding and technology transfer process than the others. Based on the condition of Palm Oil Mills in Lampung province, the most potential technology to be initially adopted is cover lagoon technology fromPT Karya Mas Energi with NPV value of Rp26,188,590,000.00; IRR 29.72%; Net B/C 1.87; Gross B/C 1.72; and PBP 4.06years.
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Judul: Methane Emissions Reduction from Palm Oil Mill  Effluent through a Biogas Plant (Case Study: Tungkal Ulu Biogas Plant, Jambi)
Abstrak: Mayoritas industri kelapa sawit di Indonesia mengolah limbah cairnya atau Palm oil Mill Effluent (POME) menggunakan sistem kolam terbuka yang melepaskan gas metana dan berpotensi meningkatkan Gas Rumah Kaca (GRK). Salah satu upaya mencegah pelepasan gas metana dari sistem tersebut adalah pembangunan proyek methane recovery, melalui Pembangkit Listrik Tenaga Biogas (PLTBg). Proyek PLTBg mendukung target pemerintah dalam menurunkan emisi GRK dan menghasilkan energi terbarukan. Penelitian ini bertujuan untuk (1) mengestimasi potensi emisi GRK dari POME sebelum adanya proyek PLTBg, (2) mengestimasi reduksi emisi GRK dari POME setelah adanya proyek PLTBg, dan (3) menganalisis kelayakan finansial proyek PLTBg. Penelitian ini menggunakan metode Clean Development Mechanism (CDM) AMS III H dan analisis cashflow. Hasil penelitian menunjukkan bahwa PLTBg Tungkal Ulu mereduksi emisi GRK sekaligus menguntungkan perusahaan. Emisi sebelum adanya PLTBg yang diestimasi dari 106.267 m3 POME adalah 44.767,80 t CO2e. Potensi reduksi emisi setelah adanya PLTBg berkisar 66,64%-74,26% pada tahun 2021-2030. Pada kurun waktu tersebut, proyek PLTBg layak secara finansial pada harga CER rendah dan tinggi. Skenario CER rendah menghasilkan nilai NPV, BCR dan IRR sebesar Rp 18,55 miliar, 1,19 dan 11,46% sedangkan CER tinggi menghasilkan nilai NPV, BCR dan IRR sebesar Rp 19,65 miliar, 1,21 dan 11,69%., Most palm oil industries in Indonesia treat Palm Oil Mill Effluent (POME) by using an open lagoon system that releases methane gas emissions and potentially increases Greenhouse Gases (GHGs). Biogas plant, a methane recovery project, becomes one measures to reduce such emissions. Biogas Plant projects support the government's target in reducing GHGs emissions and produces renewable energy. By focusing on the Tungkal Ulu Biogas, this study aims to (1) estimate the potential GHGs emissions prior the implementation of biogas plant project, (2) estimate the GHGs emissions reduction after the project implementation, and (3) to analyze the financial feasibility of the project. This study employes Clean Development Mechanism (CDM) method (i.e. the AMS III H) and cashflow analysis. The results showed that Tungkal Ulu Biogas Plant project can reduce GHGs emissions and can benefit the company. Based on 106,267 m3 of POME, GHGs emissions prior the project implementatation is 44,767.80 t CO2e. The potential GHGs emissions reduction ranges from 66.64% to 74.26% during 2021-2030. Financial analysis indicates that the project is feasible, at both low and high CER market prices. The low CER results in NPV, BCR and IRR values of 18,55 billion IDR, 1,19 and 11,46%, respectively, while high CER results in NPV, BCR and IRR values of 19,65 billion IDR, 1.21 and 11,69%, respectively.
Keyword: cashflow, CDM, GHGs, PLTBg, POME

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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