Hybrid energy site design and battery use proposal for asmall industrial zone

Today, the need for energy has become more apparent since energy usage are increasing day by day. This need has increased the competition between countries and this competition also affects the prices of energy sources. At present, the most common energy sources are scarce sources like oil, coal, petroleum, natural gas. The utilization of scarce resources in the world is considerably high. In addition to this, the damage caused by these resources in the environment is quite excessive. For these reasons, countries and international companies have directed their work to find other energy sources. Among these, renewable energy sources are the most important and sustainable ones. The most commonly used and most important ones in these studies are sun, wind, hydroelectricity. In addition to these energy sources, biomass wastes which is not common in Turkey, can be good energy source like others. This energy resources are sustainable and Turkey have good potential in these fields. In this research, we mention about sun and wind and mostly biomass resources. In biomass, there are two ways for obtaining energy from biomass. They are thermochemical and biochemical conversions. Thermochemical conversions are burning, gasification, pyrolysis and liquefaction. Biochemical conversions are fermentation and anaerobic digestion. In those days, most important and common conversion is anaerobic digestion. Anaerobic digestion, convert biomass directly into organic elements like CO2, CH4, H2S ve NH3 and methane gasses thanks to bacteria. At the end of the process, we can get clean and qualified natural gas when carbon dioxide expelled. Total energy efficiency of this conversion is 16-10%. Converting biomass into organic elements have two main steps. First step is converting organic materials into organic acids, alcohol, and CO2 with acid bacteria. In second step, those products turn into methane and CO2 thanks to methane bacteria. That methane gas has high calorific value. Every organic material has different amount of methane gas. For example, we can get higher methane percentage from oils than proteins and carbohydrates. Anaerobic digestion has good advantages but however, it has disadvantages too. For example, initial phase is very long in anaerobic digestion, difficulties making the system steady and methane bacteria are extremely sensitive to environmental conditions. Still, it's very common and commercial technology in present days. There are many different parameters effect to the anaerobic digestion. They are alkalinity, temperature, pH, toxic substances, nutrients, ammonia inhibition, sulfur, methane content, gas production and volatile acids. Best pH conditions are between 6,5 and 8,5. When pH is chanced this intervals, the process follow different pathways. In temperature, there are 3 different temperature part. They are sacrophilic (<30oC), mesophilic (35oC) and thermophilic (55oC). Changes in temperature is effects microorganisms. Because of that, we need to take special attention to the temperature. Ammonium effects mostly the methane bacteria. Gas production and methane content is quite important to measure the efficiency of the system. when the system works better, more methane gas you get. Methane in biomass must be more than 70 percent and when you get lower than that amount, reasons need to be investigated. There are many different types of anaerobic digestion bioreactors. For example, anaerobic filter, anaerobic membrane bioreactor, anaerobic lagoons, anaerobic fluidized bed reactor, anaerobic sequencing batch reactor, anaerobic sludge blanket reactor and etc. Those reactors are generally used in purification of wastewater processes. Organic solid wastes have different separation and purification processes. We can classify those separations like organic solid wastes obtained by mechanical separation, by separate collection and by separation in sources. All types of separations have different biogas production potential. We can classify organic solid wastes reactors in two different ways. They are temperatures and number of stage. In temperatures, we have mesophilic and thermophilic. In number of stages, we have 2 different types too and they are single stage and double stage systems. Those systems have similarities with wastewater processes. In biomass and biogas plants, we mentioned about mostly Europe and Asian countries. In European; countries like Norway, Italy, Switzerland, Poland, Denmark, Ireland, Australia worked on potential calculation and research about biomass. In Asia and Africa; countries like China, India, Pakistan, Malaysia, Sri Lanka, Mozambique, Kenya generally worked on obtaining energy for basic needs like heating and cooking. In Turkey, there are many studies about biomass potential calculations and researches. A study claims that 22-27% of primary energy needs can be met by biomass resources in Turkey. Biomass energy is not a process that changes depending on natural phenomena such as wind or sun. For this reason, a continuous source of energy can be obtained from biomass plants. In this study, we selected Çankırı, Şabanözü for determining the potential of producing energy from municipal, animal and vegetable wastes. In addition to biomass, a hybrid renewable energy facility has been planned with the addition of wind and solar power plants using the best incentives and aids in Turkey. The potential for the sun and the wind is calculated and the power output per hour is determined according to natural properties of Şabanözü. Domestic electricity demand is very low compared to the industrial zone because the region is usually rural. We want to meet the demand of Şabanözü Industrial Zone with this hybrid renewable energy plant. We also worked on adding energy storage system to the whole system in order to respond to the fluctuations in the electricity demand and make the energy output continuous. For this purpose, a MIP (Mix integer Programing) model was created and calculated using the MATLAB program. The battery output of the model with various scenarios, is obtained and the annual costs are determined. Three different scenarios have been used for that model and results were compared with each other. First scenario is creating a model by ignoring battery capacities which is important for electrical energy storage systems and ignoring battery state conditions like charging or discharging. Charging and discharging means when state of batteries is charging then you need to stay in that charging state for a certain time. With that constraint, changing the states is restricted. That constraint generally can be a policy of the companies or might be used as a necessity. Second scenario is created by only adding capacity constraint to the first scenario. With that constraint, amount of charging or discharging is restricted with its capacity. And the last scenario is adding charging and discharging constraint to the second scenario. Three different scenario were modeled, results compared, costs and battery quantities are viewed. As a result, model gave best solution in first scenario. But first scenario is little bit far away from real life conditions. Second and third scenarios gave the same solutions. To the comment on this, charging and discharging hours are very predictable. Because electricity demands generally increasing in days and decreasing in nights. So, the system is generally going to charging state in nights and discharging states in days. Following the determination of costs and quantities, the shortcomings of model was mentioned and it was predicted that adding stochastic models, heuristic studies or artificial intelligence would be useful in order to make the model more realistic in the future.