GNS Science Consultancy Report 2006/0XX

More documents

Recommendations

Info

2.0 ABANDONED OIL AND GAS WELLS IN OTHER COUNTRIES The idea of using abandoned oil and gas (hydrocarbon) wells and drilling wells in sedimentary basins to produce geothermal energy is not new. Low enthalpy geothermal resources in sedimentary basins in France have been tapped by wells for district heating since 1969. At present there are 41 plants in the Paris basin including 15 in the Aquitane basin and five in other regions producing hot water for a total of 200,000 households and supplanting about 170,000 TOE (Laplaige et al, 2000). Albania, Poland, Germany, Switzerland, USA, France and Australia are exploring the possibility of recovering heat from hydrocarbon wells (e.g., Bodvarrsson and Reistad, 1983; White, 1983; Barbacki, 2000; Schellshmidt et al, 2000; Lund et al, 2005). In the USA abandoned hydrocarbon wells, in regions of high heat flow (>75 mW/m 2 ) and sufficient water flow such as Texas and Oklahoma, are estimated to have a power generating potential at the gigawatt level (Appendix 2). Using the existing wells minimises the initial costs of geothermal power production. The main capital funding input is fitting existing wells with heat exchangers and small power plants (McKenna et al, 2005). In March 2006, the Southern Methodist University in Texas held the first conference on the potential of harnessing geothermal power from abandoned hydrocarbon wells (Appendix 1). 3.0 ABANDONED OIL AND GAS WELLS IN NEW ZEALAND Although the number of abandoned hydrocarbon wells in New Zealand is 50 o C in more than 150 wells drilled to depths >625m, (2) the presence of nonsaline or saline waters in most of the abandoned wells that may be discharged using artesian pressures inherent in the wells or through downhole pumps, (3) over pressuring in some wells in Taranaki (King and Thrasher, 1996), the East Coast (Field et al) and Northland (Isaac et al) indicate that some wells are artesian and will flow without the need for well stimulation or hydrofracturing, (4) mud losses during drilling indicate permeability in several wells e.g., Kiakia-1/1A in the East Coast, and (4) large areas of high heat flow cover parts of the Northland, Taranaki, Wanganui and East Coast basins in the North Island and parts of the West Coast basin of the South Island (Figures 2 and 3) where the surface conductive heat flow of >70 mW/m 2 indicate thermal gradients of >33 o C/km. 3.1 DISTRIBUTION AND DATES OF COMPLETION There are about 450 onshore and offshore abandoned hydrocarbon wells in New Zealand (Figure 3). Of these wells, 349 are onshore with the offshore wells drilled mostly in waters
Figure 3. Distribution of offshore and onshore abandoned wells in various hydrocarbon basins (data from http://www.crownminerals.govt.nz). Figure 4. Number of offshore and onshore abandoned wells in New Zealand. GNS Science Report 2007/23 5
Page 2 and 3: Abandoned oil and gas wells - a rec
Page 4 and 5: CONTENTS ABSTRACT..................
Page 6 and 7: ABSTRACT There are 349 abandoned on
Page 8 and 9: Figure 1. Temperature, depth and pe
Page 12 and 13: Figure 5. Map showing the distribut
Page 14 and 15: Figure 6. Drilled vertical depths o
Page 16 and 17: Figure 8. Temperatures ranges of on
Page 18 and 19: Table 1. Number of wells within a r
Page 20 and 21: 3.3 REASONS FOR ABANDONING WELLS Mo
Page 22 and 23: Assuming a flow of 4 L s -1 , the 2
Page 24 and 25: 5.0 CURRENT GEOTHERMAL USE OF ABAND
Page 26 and 27: In New Zealand temperature may be p
Page 28 and 29: Figure 16. Abandoned hydrocarbon we
Page 30 and 31: 10. Determine how geothermal produc
Page 32 and 33: Isaac M J, Herzer R H, Brook F J an
Page 34 and 35: APPENDIX 1 NOTES ON THE GEOTHERMAL
Page 36 and 37: Speaker Company/Agency Topic Main P
Page 38 and 39: Table 6. Basic well data for onshor
Page 40 and 41: Well Name NORTH ISLAND TARANAKI Dat
Page 42 and 43: Well Name SOUTH ISLAND WEST COAST D

GNS Science Consultancy Report 2006/0XX

Create successful ePaper yourself

Delete template?

Save as template?