Proposed by Dr Peter Martin
All oil wells produce fluids that are normally hotter than the ambient surface temperature. lf the volume of fluid is sufficient and the temperature differential (delta-T) high enough, then useful energy could be extracted.
The current worldwide production of oil averages 13 million cubic metres per day. Estimates for the volume of water produced at surface from oil and gas wells vary between 90 to 130 million cubic metres – many times that of the associated oil extracted. While temperatures vary widely depending on the depth of the reservoir, many fields have wellhead fluid temperatures at, or exceeding, 100°C.
Capturing low-grade Heat Energy
Could equipment be developed that could produce electricity from heat sources with a delta-T of 70°C? Although outline theories have been developed to exploit heat from oil field fluids, to-date no company has engineered a working commercial system.
The advantages of developing a new electricity generating system are:
Many oil operations generate electricity using available gas or diesel and as a result produce large volumes of CO2. The use of hydrocarbons means burning product that could otherwise be sold. Offshore generation is complicated by space limitations on platforms and the availability of suitable fuels. Data exists from one mid-size North Sea installation indicating that the bill for imported electricity has reached £5 million per annum.
Potable (drinking) Water
As described above, vast volumes of oily and saline water are produced in oil and gas fields. Purification using cyclone separators and reverse osmosis although highly effective demands considerable energy input. Powering these processes by a novel electricity generating system using elevated temperature connate waters would result in potable water at low cost and no CO2 generation. There is a huge opportunity to provide water to communities in oil rich but water scarce regions, producing low salinity water offshore and in many arid settings.
Could equipment be developed that could produce electricity from heat sources with a delta-T of 70°C?
Although outline theories have been developed to exploit heat from oil field fluids, to-date no company has engineered a working commercial system. This challenge will work to do just that: by combining modified existing components with oilfield knowledge and identified demand to jump start a major initiative across the oil sector.
A computational model and associated mathematical outputs to support the selected means through which electricity can be most efficiently generated via connate (trapped in pores of rock) waters.
In terms of mathematics outputs, it is expected that the ‘system’ (idea) to be underpinned by appropriate scientific detail/justification, including considerations for efficiency, cost and viability. This model would go alongside any design proposals that the team would complete.
- Connate Water in Oil and Gas Sands, Ralph J. Schilthuis Trans. 127 (01): 199–214. Paper Number: SPE-938199-G. https://doi.org/10.2118/938199-G
- Thermoelectric power generation: Peltier element versus thermoelectric generator, Marco Nesarajah and Georg Frey. IECON 2016 – 42nd Annual Conference of the IEEE Industrial Electronics Society, 10.1109/IECON.2016.7793029
- Heat Transfer Fundamentals for Electro-thermal Heating of Oil Reservoirs, B.C.W. McGee and R.D. Donaldson, Canadian Petroleum Conference. PETSOC-2009-204. https://doi.org/10.2118/2009-204