Energy in South Australia and trap in the deeper heat. Due to the low permeability of granite, the hot rocks must undergo hydraulic fracturing and be stimulated to allow a flow of water through the system to produce energy. This heat is slowly conducted to shallower rocks near the surface. Petratherm propose developing the geothermal energy in the more permeable sedimentary rocks that overlay the hot granite, a process called Heat Exchange Within Insulator (HEWI). While somewhat cooler, in many cases they do not require hydraulic fracturing. It is estimated that one percent of geothermal energy shallower than five kilometres below the earth's surface
Notes from the Underground (creative writing paper) Sutherland agreed with James that 'everything in the paper is worth reading' but felt the newspaper was pitched too highly compared to other free newspapers. 'It might work, but I think the title is an allusion to the Dostoevsky book Notes from Underground which I suspect would probably go over the heads of most commuters.' However he did add that 'this is a very good platform for new literature, and I am all in favour of it. More power to it, I say.' Notes from the Underground (creative writing paper) Notes from the Underground is a creative writing free newspaper.