ФОРСАЙТ ПІДВИЩЕННЯ ЕНЕРГОЕФЕКТИВНОСТІ БУДІВЕЛЬ НА БАЗІ ЕНЕРГОХАБА УНІВЕРСИТЕТУ

The article reveals the essence of the key motivation drivers to save energy and increase the energy efficiency in higher education institutions. In particular, a low level of interest of higher education institutions in the implementation of strategies to reduce energy consumption has been observed. The findings suggest that the lack of interest in energy saving is primarily affected by budget legislation since the energy cost calculation was based on the consumption norms for a particular budgetary institution and the current (planned) electricity and heat tariffs. Recently, it has been decided that from now on universities will not obtain budget funding to cover utility costs; the amount of subsidies from the Ministry of Education and Science of Ukraine for the implementation of the government objectives will comprise regulatory costs for public service provision according to the student contingent. Standard property maintenance costs will not be covered by the Ministry anymore which will impose the burden of paying the utility bills upon the University’s gross income. Hence, there is a need to take efforts to enhance energy efficiency and energy saving in higher education institutions which was implemented using a foresight methodology. Within the scope of this study, the foresight project to improve the energy efficiency of buildings in the frameworks of the University energy hub is based on the following calculations: thermal energy consumption for heating public buildings, estimated hourly heating load to ensure heating in the building, verifying the feasibility of heating standby regulation, measuring energy savings through the creation of an automated heat supply station, as well as annual savings in monetary terms. In order to save resources and boost energy efficiency based on the University energy hub using an automated heat supply station, the study offers a mathematical toolkit to justify the choice of minimum and maximum values of optimal microclimate parameters; reduce infiltration, increase the efficiency of indoor air distribution; optimal modes of local air conditioning, preheating and cooling; utilizing of "waste" and natural heat and cold; "combining" microclimate systems with other systems; improving automation devices in technical systems. It is argued that increasing the energy efficiency of heating systems in University buildings on the basis of its own energy hub will contribute to gaining significant savings in thermal energy for heating and significantly reduce carbon dioxide emissions into the environment. In addition, the study reveals that the cost of thermal energy for heating depends upon a building design, modernization quality, reconstruction and insulation, applied building materials, spatial planning solutions, the presence or absence of control and automated systems, maintenance systems and attitude of owner’s attitude to innovations. The conclusions summarize that the cost of thermal energy can vary significantly in buildings of the same type.

Simulations of Heat Supply Performance of a Deep Borehole Heat Exchanger under Different Scheduled Operation Conditions

With the changing world energy structure, the development of renewable energy sources is gradually accelerating. Among them, close attention has been given to geothermal energy because of its abundant resources and supply stability. In this article, a deep borehole heat exchanger (DBHE) is coupled with a heat pump system to calculate the heat supply and daily electricity consumption of the system. To make better use of the peaks and valleys in electricity prices, the following three daily operating modes were studied: 24-h operation (Mode 1), 8-h operation plus 16-h non-operation (Mode 2), and two cycles of 4-h operation and 8-h non-operation (Mode 3). Simulation results show that scheduled non-continuous operation can effectively improve the outlet temperature of the heat extraction fluid circulating in the DBHE. The heat extraction rates of Mode 1 is 190.9 kW for mass flowrate of 9 kg/s; in Mode 2 and Mode 3 cases, the rates change to 304.7 kW and 293.0 kW, respectively. The daily operational electricity cost of Mode 1 is the greatest because of 24-h operation; due to scheduled non-continuous operation, the daily operational electricity cost of Mode 3 is only about 66% of that of Mode 2. After an 8-month period without heating, the formation-temperature can be restored within 4 °C of its original state; 90% recovery of the formation-temperature can be achieved by the end of the second month of the non-operation season.

Improving a heat supply system by increasing the efficiency of the heat pump unit

The reliability and efficiency of the operation of district heating systems is largely determined by the efficiency of preparation of heating network water. In open heat supply systems, make-up water, among other things, compensates for the water intake in hot water supply systems. A number of technologies have been developed that increase the efficiency of an open heat supply system by reducing the water consumption in the supply pipeline of the heating network, increasing the operating time of the heat pump, and increasing the specific generation of electricity for heat consumption at the CHP plant due to additional cooling of the network water in the return pipe of the heating network.

Risk of Business Bankruptcy

Recently, the demand of business owners to ensure the sustainability of their businesses has come to the fore. It results in a focus on identifying the risks of businesses' financial failure. Several prediction models can be applied in a given area. Which of these models is most suitable for Slovak companies? The aim of this chapter was to point out the possibility of applying the DEA method in measuring the financial health of companies and predicting the risk of their possible bankruptcy. The research was carried out on a sample of companies operating in the field of heat supply. The indicators were selected using related empirical studies, a univariate Logit model, and a correlation matrix. In this chapter, two main models were applied: the DEA model and the Logit model. The main conclusion of the paper is that the DEA method is a suitable alternative in assessing businesses' financial health.

RENEWABLE ENERGY INTEGRATION FOR HOT WATER SUPPLY AND HEATING OF BUILDINGS

Solar energy is widely used in solar systems, where economy and ecology are combined. Namely, this represents an important moment in the era of depletion of energy resources. The use of solar energy is a promising economical item for all countries of the world, meeting their interests also in terms of energy independence, thanks to which it is confidently gaining a stable position in the global energy sector. The cost of heat obtained through the use of solar installations largely depends on the radiation and climatic conditions of the area where the solar installation is used. The climatic conditions of our country, especially the south, make it possible to use the energy of the Sun to cover a significant part of the need for heat. A decrease in the reserves of fossil fuel and its rise in price have led to the development of optimal technical solutions, efficiency and economic feasibility of using solar installations. And today this is no longer an idle curiosity, but a conscious desire of homeowners to save not only their financial budget, but also health, which is possible only with the use of alternative energy sources, such as: double-circuit solar installations, geothermal heat pumps (HP), wind power generators. The problem is especially acute in the heat supply of housing and communal services (HCS), where the cost of fuel for heat production is several times higher than the cost of electricity. The main disadvantages of centralized heat supply sources are low energy, economic and environmental efficiency. And high transport tariffs for the delivery of energy carriers and frequent accidents on heating mains exacerbate the negative factors inherent in traditional district heating. One of the most effective energy-saving methods that make it possible to save fossil fuel, reduce environmental pollution, and meet the needs of consumers in process heat is the use of heat pump technologies for heat production.

Mobile Thermal Energy Storage

The article is devoted to topical issues related to the storage, accumulation and transportation of heat by stationary and mobile heat storage. Analysis of the current state of the district heating system indicates significant heat losses at all stages of providing the consumer with heat. The use of heat storage in heat supply systems leads to balancing the heat supply system, namely, the peak load is reduced; heat production schedules are optimized by accumulating excess energy and using it during emergency outages; heat losses caused by uneven operation of thermal equipment during heat generation are reduced; the need for primary energy and fuel consumption is reduced, as well as the amount of harmful emissions into the environment. The main focus is on mobile thermal batteries (M-TES). The use of M-TES makes it possible to build a completely new discrete heat supply system without the traditional pipeline transport of the heat carrier. The defining parameters affecting the efficiency of the M-TES are the reliability and convenience of the design, the efficiency and volume of the “working fluid”, the operating temperature of the MTA recharging and the distance of transportation from the heat source to the consumer. The article contains examples of the implementation of mobile heat accumulators in the world and in Ukraine, their technical and technological characteristics, scope and degree of efficiency. The technical indicators of the implemented project for the creation of a mobile heat accumulator located in a 20-foot container and intended for transportation by any available means of transport are given.

ENERGY EFFICIENCY OF COMBINED HEAT SUPPLY SYSTEMS

The consumption of energy resources in the world states is constantly growing from year to year. The production of fossil fuels is also increasing, but for various reasons it cannot fully cover the required amount from consumers. One of the most important consumption sectors is heat loads from heating, ventilation and hot water supply of industrial and residential buildings. To cover the thermal loads of heating and hot water supply, the necessary heat carrier is water heated to a certain temperature. The most promising from the point of view of heating water for hot water supply are solar collectors. Hot water for heating needs to be reheated practically throughout the entire heating period. The introduction of heat pumps is promising. When using solar collectors, the heating agent can be reheated in heat pumps. The aim of the study is to develop such a combined heat supply system that uses more renewable energy and as a peak source a fossil fuel boiler (electric energy), as well as a method for calculating this system to determine the optimal composition of equipment and rational modes of its operation. The methodology for calculating heat supply systems combining solar collectors, heat pumps and fossil fuel boilers is presented. The problem of load distribution between the main elements of the combined heat supply system should take into account the probabilistic component. This is due to the fact that with a changing real mode of operation, different thermal load of the equipment can be optimal. This is primarily influenced by the variable heat inputs from solar collectors during the day. According to the above method, it is possible to determine the optimal parameters of the heat supply system for different operating modes, at which the minimum consumption of fossil fuel will be ensured.

ANALYSIS OF EXISTING SOLUTIONS FOR IMPROVING THE MEASURING AND COMPUTING COMPLEXES OF HEAT SUPPLY NETWORKS

In the presented article, the team of authors considers the existing methods and the main modern technical solutions that are currently implemented in different countries in the diagnosis of heat supply networks. There is a selection of the main directions in the development and design of heat supply networks, which have already been implemented or supported by scientific teams from different countries. Various methods and technical features of diagnostics are reviewed, strengths and weaknesses of the presented solutions are highlighted. The reviewed works were subjected to detailed analysis, which revealed the presence of a high interest of the scientific and industrial community in the integration and improvement of existing digital technologies in the development of heat supply systems, which would be closely related to forecasting and modeling processes in this industry. The team of authors highlights the main vectors for the development of this sector, citing an example of a significant increase in the degree of digitalization of final products, which makes it possible to use data analytics to obtain effective technical solutions regarding heat supply networks. Separately, the positive experience of different countries in this industry is noted when using neural networks not only in the design of heat supply networks, but also as a target industry as a whole. Assumptions are put forward about the need for a detailed analysis of the existing foreign and domestic experience, as well as scientific developments in this area, in order to determine the most suitable technical solutions on the territory of the Russian Federation, which will take into account the climatic characteristics of the country and be based on methods of large data analysis, computer vision and simulation. modeling.