No abstract

Engineered Geothermal Systems (EGS) are promising, but high-risk targets for baseline energy generation. Technology breakthrough is needed to lower the high risks from largely unknown geologic variables and the limited control of the coolant flow field underground. A new, robust EGS (REGS) arrangement and creation technology is reviewed featuring innovative fracture opening, stabilization and permeability control. The geometry, aperture support technique and coolant fluid flow isolation system are all robustly planned and created according the inventive concept. The new elements of the REGS technology are (1) the step-by-step creation, control, and tests of hydraulic fracturing to achieve a planar wing fracture or fractures osculating along the well trajectory; (2) fracture stabilization by hardening grouting injection to create a central support island in each planar wing fracture for zonal isolation; and (3) well-fracture-well fluid circulation for geothermal energy extraction from single, or clustered planar fractures as geothermal heat exchangers. The paper reviews ongoing tests to prove the key components of the REGS geologic heat exchanger with stabilized, large fracture aperture and controlled flow zones for minimized opening pressure loss, seismicity and maximized energy extraction. Flow fields and heat transport are reviewed around zonal isolation of fracture flow by a grouted, blocking island for heat exchange. The robustness is reviewed for the step-bystep construction of a REGS. The paper reports new results from using numerical, coolant flow and heat exchange models to demonstrate the geothermal energy potential of a single REGS well drilled in hot, dry rock.

Munkánk célja a megosztott e-taxi szolgáltatások innovatív megoldásainak vizsgálata. Ehhez összegyűjtöttük a megosztott elektromobilitásra vonatkozó nemzeti és európai uniós szakpolitikákat, ösztönzőket, stratégiákat és trendeket. Elsőként a jelenleg elérhető (e-) autómegosztó rendszerek terjedését és a Covid-19 világjárvány hatásait mutattuk be. Ezután a fenntartható taxizást vizsgáltuk, az egyik hazai példa a London Electric Vehicle Company (LEVC) által gyártott TX elektromos taxi volt, amelynél az üzemeltetési költség, illetve CO2 kibocsátás-megtakarítást a hagyományos taxikhoz viszonyítva számítottuk ki. A világjárvány után várhatóan felgyorsul a fejlett önvezető technológia elterjedése és ez a változás új lehetőségeket fog hozni. Ezért áttekintést készítettünk az ilyen komplex hatású innovatív technológiákról, hogy feltárjuk az e-taxi szolgáltatások alkalmazási feltételeit, a benne rejlő lehetőségeket és veszélyeket. Végül javaslatokat fogalmaztunk meg a hazai gyakorlatba való átültethetőségre vonatkozóan.

Waste-management and energetics are among the most important fields in the case of sustainable development, which is a popular slogan and aim of our society nowadays. Large amount of waste is generated by all branches of economy constantly. However, the deposition of this has not been solved yet as well as there are plenty of questions in energetics. Of course there are many efforts to settle our main problems; one of these can be systems that handle the two topics simultaneously.Index terms: Biogas, Energy dependence, Incinerator, Waste management I. THE IDEABasically the idea is about the utilization of the remaining energy of our waste and about a way how we could optimize our waste-management to produce energy. If we look into the Waste Framework Directive of the European Union, published in 2008 [1], it defines the hierarchy of waste, which means 5 or 6 different options in priority order in waste-management. This article is mainly about the options of energy recovery and disposal. Energy recovery depends on practically two factors, the way of recovery and the content of the material. After this we can prepare the grouping of waste based on the location of processing, and then we can prepare groups based on its content. Firstly, if we examine the content of our garbage we can determine two types; there is a part of our waste which can be fermented in a fermenter, producing biogas and there is a part which can only be processed in plants that are dedicated to incineration. After the definition of the demanded facilities, we have to study different parts of our waste based on which facility we can utilize it in. According to this, we are able to divide our garbage into 5 groups. About the domestic solid waste we can determine two main types, organic and nonorganic solid waste. Besides maximizing energy production we cannot forget studying it based on the calorific value of the different components. Considering the negative effect of glass and metal on the resultant calorific value [2] we must say that these two materials should be recycled or reused. Apart from our solid garbage our society produces huge amount of liquid refuse (sewage-water) as well. Of course in a basically agricultural country like Hungary, besides domestic waste, considerable amount of agricultural residues is also developed. This type can also be applied as additional raw material in our waste-based energy production. So the main idea can be to provide energy for a town using its own waste. Of course as it is deduced in the previous paragraph the infrastructural demands are an incinerator, a fermenter and a huge infrastructural background. The raw materials are our domestic solid waste, sewage sludge and agricultural residues. The system which can be seen on Fig. 1. and which is worked out in this article, provides 3 forms of secondary energy. The fermenter unit produces biogas while in the incinerator, electricity is provided. During the energy conversion considerable amount of waste heat is also developed. This heat can be used for dist...