Tomislav Pukšec

Economic viability and geographic distribution of centralized biogas plants: case study Croatia

Current promising increase of agricultural investments in Croatia not only leads us to the implementation of new technologies and procedures but also leads to an increase of public awareness toward modern agricultural production. As a side effect, renewable energy sources, with special emphasis on biogas, are quickly coming under the loop. Because of this effect, a question of total biogas potential for the farming sector in Croatia becomes very important. One of the biggest obstacles in utilizing biogas on Croatian farms is its geographical displacement and small size. Through this paper economic viability and geographical distribution, as key parameters in determining realistic biogas potential on family farms, will be presented with special emphasis on the two most promising farming sectors: cows and pigs. As already mentioned, one of the biggest barriers in utilizing biogas in Croatia is the relatively small size of farms that are not capable of having economically viable biogas production. That is why community biogas plants will be important in increasing biogas utilization in Croatian farming sector. Presented methodology represents basics for regional analysis of biogas potential of a farming sector with Croatia as a case study with cost assessment of community biogas power plants considering transport distances, transport costs, and size of the power plants and family farms involved in community biogas production. The value of finding Croatia’s farming biogas potential is also important since farms are high-volume energy consumers in their everyday operations and part of that energy consumption can be compensated from renewable energy sources like biogas.

Modelling energy demand of Croatian industry sector

Industry represents one of the most interesting sectors when analysing Croatian final energy demand. Croatian industry represents 20% of nation’s GDP and employs 25% of total labour force making it a significant subject for the economy. Today, with around 60 PJ of final energy demand it is the third most energy intensive sector in Croatia after transport and households. Implementing mechanisms that would lead to improvements in energy efficiency in this sector seems relevant. Through this paper, long-term energy demand projections for Croatian industry will be shown. The central point for development of the model will be parameters influencing the industry in Croatia. Energy demand predictions in this paper are based upon bottom-up approach model. IED model produces results which can be compared to Croatian National Energy Strategy. One of the conclusions shown in this paper is significant possibilities for energy efficiency improvements and lower energy demand in the future.

Integrating the flexibility of the average Serbian consumer as a virtual storage option into the planning of energy systems

With the integration of more variable renewable energy, the need for storage is growing. Rather than utility scale storage, smart grid technology (not restricted, but mainly involving bidirectional communication between the supply and demand side and dynamic pricing) enables flexible consumption to be a virtual storage alternative for moderation of the production of variable renewable energy sources on the micro grid level. Study, motivated with energy loss allocation, electric demand and the legal framework that is characteristic for the average Serbian household, was performed using the HOMER software tool. The decision to shift or build deferrable load rather than sell on site generated energy from variable renewable energy sources to the grid was based on the consumers net present cost minimization. Based on decreasing the grid sales hours of the micro grid system to the transmission grid from 3, 498 to 2, 009, it was shown that the demand response could be included in long-term planning of the virtual storage option. Demand responsive actions that could be interpreted as storage investment costs were quantified to 12 €/year in this article.

Integration of Desalination and Renewables, a Demonstration of the Desalination Module in the H2RES Model: Case Study for Jordan

Water scarcity and the dependence on fossil fuels as a primary source of energy are crucial problems for a number of arid countries. The integration of energy and water systems presents a possible solution for both issues. The flexibility of a desalination system can increase the possibility for the penetration of intermittent renewable energy sources and thus provide both fresh water and the potential for the local production of clean energy. Jordan is the fourth most water deprived country in the world and is also highly dependent on energy import. Almost all of its primary energy comes from imported fossil fuels, mostly from natural gas. It is a country rich in wind and solar energy but unfortunately, almost no utilization of that potential. The integration of desalination systems and renewable energy sources is a possible solution both for Jordan’s water and energy supply. The goal of this paper is to demonstrate the desalination module in the H2RES model using Jordan as a case study. H2RES is a flexible energy modelling tool used for the balancing of energy supply and demand on an hourly basis. It is capable of demonstrating the benefits of water and energy integration for the purpose of increasing the penetration of intermittent renewables and the reduction of CO2 emissions. For this purpose, four scenarios have been created. The first one is a business as usual scenario with no desalination, a desalination scenario and two desalination scenarios that utilize the produced brine as energy storage in pump hydro plants. The results will show that the utilization of desalination, especially in the case where desalination is combined with pump storage, can help increase the penetration of renewable energy sources into the electrical grid and thus help decrease the dependence on energy import and reduce the CO2 emissions of the energy system.

Economic Viability and Environmental Impact of Centralized Biogas Plants in Croatia

Biogas plants are an established technology and their benefit is well recognized but they are still underutilized in Croatia, mostly due to the specific state of its agricultural sector. They can reduce the environmental impact of a farm, help with manure management and can also be an extra source of income to the owner. The biggest problem for Croatian farms is their small size and because of that, the supply of the plant with the necessary substrate. The utilization of centralized biogas plants is a possible solution to this problem. There are several factors that can influence the economic viability of a biogas plant ranging from its size to the modes of transport used to supply it with raw material. Because of this, the design of the plant and its operation has to be carefully planned in order to guaranty its economic viability. The goal of this work is to analyze the impact of the transportation distances on the economic viability of biogas plants and the resulting reduction of greenhouse gas emissions. Three hypothetical centralized biogas plants with installed electrical powers of 250 kW, 500 kW and 1 MW have been analyzed. Different transportation distances and different transport efficiencies have been taken into account.

Economic Viability of Centralized Biogas Plants: A Case Study for Croatia

Biogas plants are an established and widely used technology in a number of European countries, but their utilization in Croatia is hampered by the state of its agriculture sector. Small farms, often with less than 15 heads of cattle, are common and they are not capable of independently running a biogas plant. For that reason, centralized biogas plants could present a viable option for smaller farms like the ones mostly present in Croatia. The utilization of biogas can have a number of positive effects on the day to day operations of a farm. Biogas plants can reduce the carbon footprint of a farm, help with manure management and additionally, they can provide a source of income to the owner. Since they present a sizeable investment, it is crucial to properly evaluate the feasibility of such investments. The goal of this work is to evaluate and present the impact that the size of the plant, content of manure in the substrate, the transport distance and efficiency have on the economic viability of centralized biogas plants. A case study for Croatia has been created for this purpose. The results will demonstrate the economic viability of larger biogas plants and the high impact transport has on it.

Building smart energy systems on Croatian islands by increasing integration of renewable energy sources and electric vehicles

In the Croatian territory of Adriatic Sea there are 49 inhabited islands with a total population of 124,955 people according to the census from 2011. Many studies and analyses showed that inhabited Croatian islands can all meet their energy needs from locally available renewable energy sources. Studies have been done for the islands of Krk, Unije, Losinj in the North Adriatic, and Mljet, Lastovo and Korcula in the south Adriatic Sea. Building the smart energy systems on the Croatian islands has become crucial in order to increase penetration of renewable energy sources and make local transport more sustainable. In the first part, the paper presents results of modelling of energy systems in Croatian islands with a high share of renewable energy sources, energy storage, hydrogen and electric vehicles. In the second part, the paper brings results of proposed financial mechanisms and strategies for building smart energy systems.

Establishing an assessment framework for energy sustainability in prisons: The E-SEAP project

Prison sites are a special type of public buildings or facilities in general that are overlooked by policy makers. The prison size and constant energy use results in excessive energy consumptions, which implies that a focus on such sites is necessary. Most authorities rather focus on the security aspects of prison estates than their energy efficiency, and this is transferred naturally to all members of the prison community, i.e. staff and their families, prisoners and their families and wider community. In this context, the European Sustainable Energy Award for Prisons (E-seaP) is an Intelligent Energy Europe project that deals with the sustainable energy behavior of prison sites in 8 European regions. The main goal is to devise an assessment framework for energy sustainability in prisons using a holistic approach, which takes into consideration not only the building energy management but also the provision for education and training and the wider community impact. This paper presents the adopted assessment framework along with a comparison of energy consumption in 17 prison sites in Europe. The assessment procedure may be adapted for use also in other types of public buildings.