PDF Publication Title:
Text from PDF Page: 017
116 Chapter 1 Synopsis and Executive Summary 1.4 Estimating the Recoverable Portion of EGS possible to achieve more than 75% savings in electrical energy consumption per unit of heating or cooling delivered to the building. Because the use of geothermal heat pumps is often treated as an energy efficiency measure rather than as energy supply – and because they are readily available commercially – more than 1 million units had been installed in the United States by the end of 2005. For a geothermal resource to be viable, in addition to having sufficiently high temperature, in situ hydrologic and lithologic conditions need to be favorable. In existing vapor and liquiddominated hydrothermal systems, this amounts to having a rock system (reservoir) that has high permeability and high porosity filled with steam or water under pressure. If such conditions do not exist naturally, then the rock system must be stimulated to generate or modify a reservoir to make it sufficiently productive. This is the essence of EGS, where the reservoir is engineered to have it emulate the productivity of a viable hydrothermal system. A range of lithologic and geologic properties are important for determining EGS stimulation approaches. Most important, the state of stress at depths of interest must be known. In addition, other features of the rock mass that influence the probability of creating suitable interwell connectivity include natural fracture spacing, rock strength, and competence. Estimating the recoverable fraction of any underground resource is inherently speculative, whether it is for oil or gas, geothermal energy, or a specific mineral. Typically, some type of reservoir simulation model is used to estimate how much can be extracted. To reduce errors, predicted results are validated with field data when available. This type of “history matching” is commonly used in reservoir analysis. Sanyal and Butler (2005) have modeled flow in fractured reservoirs using specified geometries to determine the sensitivity of the calculated recoverable heat fraction to rock temperature, fractured volume, fracture spacing, fluid circulation rate, well configuration, and poststimulation porosity and permeability. They used a 3dimensional finite difference model and calculated the fraction of the thermal energy in place that could be mined for a specified set of reservoir properties and geometry. Interestingly, for a range of fracture spacings, well geometries, and fracture permeabilities, the percentage of recoverable thermal energy from a stimulated volume of at least 1 x 108 m3 (0.1 km3) under economic production conditions is nearly constant at about 40 ± 7% (see Figure 3.1). Furthermore, this recovery factor is independent of well arrangements, fracture spacing, and permeability, as long as the stimulated volume exceeds 1 x 108 m3 – a value significantly below what has been already achieved in several field projects. The SanyalButler model was used as a starting point to make a conservative estimate for EGS resource recovery. Channeling, short circuiting, and other reservoirflow problems sometimes have been seen in early field testing, which would require remediation or they would limit capacity. Furthermore, multiple EGS reservoirs would have a specified spacing between them in any developed field, which reduces the reservoir volume at depth per unit surface area. Given the early stage of EGS technology, SanyalButler estimated 40% recovery factor was lowered to 20% and 2% to account for these effects, and reservoir spacings of 1 km at depth were specified to provide a more conservative range for EGS. With a reservoir recovery factor specified, another conservative feature was introduced by limiting the thermal drawdown of a region where heat mining is occurring. The resource base figures given in Table 1.1 use the surface temperature as the reference temperature to calculate the total thermal energy content. A much smaller interval was selected to limit the amount of energy extracted by specifying a reservoir abandonment temperature just 10°C below the initial rock temperature at depth.PDF Image | Synopsis and Executive Summary
PDF Search Title:
Synopsis and Executive SummaryOriginal File Name Searched:
egs_chapter_1.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)