The world’s first closed-cycle geothermal heat recovery system has been put in place by the engineers of MS Energy Solutions Ltd. in a barren oil and gas prospecting well. The implementation of the 0.5 MW heat producing system of the “WeHEAT (Wells for Heat Exchanging Advanced Technology)” type technology developed by the company is an outstanding achievement because it enables the utilisation of out-of-use deep drilling projects without the extraction of the formation water.
The thermal heat plant now put in place in a deep wellbore at Kiskunhalas in the 1960s is a 100% green renewable energy producing system. The system generates zero carbon energy sustainably, without any emission whatsoever, achieving a 96% efficiency ratio when used directly for heating. Its operation needs no energy generated from fossil fuels and its life cycle spans over generations of human life. This small facility, snugly fitting in with its landscape environment, generates energy without any waste output at all.
The mini heat plant technology developed through four years of engineering efforts may come as a great opportunity for local governments, agricultural businesses and other private companies because this solution enables cutting the heating bills of public institutions, factories and homes to nearly zero. This is particularly advantageous for agricultural businesses because the energy profile of the heating plant is very closely in line with the energy demand of agriculture, particularly horticultural entities.
The utilisation of abandoned deep wellbores or dry holes for geothermal energy generation purposes has so far been accomplished by transforming them into water wells. This technology has expanded the range of possibilities, while other statutory and environmental tasks entailed by extracting water, or the costs and risks of boring new deep wells, do not have to be faced in implementing heating systems.
The installation of the “WeHEAT” type heat generating system on an existing well provides the well with a 300-900 kW thermal energy generating capacity. Such an amount of energy is enough to heat a structure of a floor area of about 15 thousand square metres with a poor energy insulation system (e.g. greenhouse) or a building complex with an efficient heat insulation system, of a floor area of up to 50-60 000 square metres, such as a condominium consisting of 600 apartments.
Nearly all of the widely used geothermal technologies – technologies utilising the thermal energy of the earth – are based on water extraction where formation water is used as working fluid. Although this involves a very significant degree of enthalpy, the lack of due care in the water treatment processes, production systems without reinjection, the discharge of inadequately treated water into surface recipient water bodies as well as occasional auxiliary gas (methane, carbon dioxide) release, often cause major damage to the ecosystems concerned, while proper water treatment is a major expenditure item in the economic calculations of such projects.
he WeHEAT technology developed by MS Energy Solutions Ltd. however, does not require water extraction. It is a completely closed loop system: although it can extract less energy than the conventional geothermal system, it is by far more predictable, it does not entail water treatment obligations and costs, or environmental pollution, and it does not jeopardise valuable water resources, it is carbon-neutral and generates no waste. The system entails no environmental impact and its life cycle ratio is highly advantageous. The cost of the implementation of this type of technology is about 10 percent of that of other types of geothermal systems, with practically negligible risks.
The development of the new technology will greatly benefit both the geothermal sector and the hydrocarbon industry. There are numerous sites where good strata holding hot formation water are not accessible; in such places programmes for the reuse of wells already bored and paid for, that is, expensive but barren projects, might constitute meaningful investment projects for any average domestic agricultural or industrial enterprise.
