Andrzej Gonet

Theoretical Model of Borehole Heat Exchanger

The paper deals with the possible use of existing oil wells for geothermal energy production. A mathematical model, describing the process of exploitation of a borehole heat exchanger, has been worked out. It was used for determining energy efficiency, employing the main parameter, i.e., flow of produced heat energy. The results of simulation of borehole heat exchanger operation in deep conditions of Iwonicz Zdroj fields depleted deposits (Polish Carpathians) are presented. A considerable part of oil deposits in the Carpathian region-a cradle of the worlds oil industry-are to be decommissioned. Owing to the high density of population, the wells are planned to be adapted for borehole heat exchangers for clean energy production for local purposes. The decommissioning costs will be avoided.

Deep Borehole Heat Exchangers — A Conceptual and Comparative Review

Borehole heat exchangers (BHEs) are used for transforming a rock mass into an underground heat storage. Usually, their depth does not exceed 200m, but some extend to a depth of almost 3000m. Underground heat storages can operate as part of heating and cooling systems, often economically. In winter they extract heat from the rock mass for space heating, while in summer the cooled rock mass is used for air conditioning. The heat extracted from buildings via air conditioning is transferred into the rock mass, thereby regenerating its condition for winter time. Deep borehole exchangers also may operate only in the heating mode. Then, the rock resource conditions are regenerated via heat transfer through neighboring rocks. If a groundwater flow is present, the heat can also be removed and the source conditions regenerated through convection. Here, an overview of the use and operation of deep BHEs around the world is provided. Special emphasis is placed on the Carpathians, where numerous analyses of geothermal heat use have been performed since 1999. Examples of calculations for old oil and gas wells as well as negative exploration boreholes are given. Such analyses have been performed for boreholes in Poland and the Ukraine. However, little research has been published on this subject to date, for reasons described herein.

The Experimental Results of the Functional Tests of the Mole Penetrator KRET in Different Regolith Analogues

Depending on the specific region, the unmanned exploration of the planetary bodies can be divided into three groups: operations above the surface, operations on the surface and operations under the surface. In this chapter we will focus on the operations under the surface, connected with them requirements, available technology and possible output from such research. In this context we will present mole KRET device as a one of the possible solutions for low power consuming device which can be treated as a sub-surface end-effector of a more complicated robotic system. The experimental results of the functional tests of the mole in a 5 m test-bed system will be provided for different regolith analogue. The detailed investigation of lunar analogue will show how the progress of the mole depends on the compaction ratio of the material.

POSSIBILITIES OF HEATING AND AIR-CONDITIONING OF BUILDINGS IN THE MOUNTAIN AREAS

Summary The mountain areas, due to their specificity, require special approach to issues concerning heating and air-conditioning of buildings. After presenting general information on demand for heat in a standard residential building, the forecasting of demand for final energy by particular branches of economy has been presented. Fossil fuels are most commonly used in heating buildings. In this kind of systems the heat is supplied to the consumer by means of heating pipes provided by heat power stations or combined heat and power stations or it is generated in boilers owned by the consumers. The remote heat source can also be energy from geothermal power station, as it is in the Podhale region. There is an alternative solution to these systems in the form of heat pumps that are often connected to borehole heat exchangers. Depending on the energy balance of the heating system and air-conditioning of a particular building the latter system can be additionally aided by solar collectors. This method requires only a power service connection, which is available almost in every building. Moreover, practical uses of the proposed system, which should be more widely applied in the mountain areas, have been described.