NET Power LLC recently announced that technology manufacturer Toshiba Corporation has joined The Shaw Group, a global engineering services firm, and Exelon Corporation, the U.S. competitive energy provider, to develop NET Power’s gas-fired power generation technology with zero emissions.
The technology utilizes a new, oxyfuel, high pressure, supercritical carbon dioxide cycle, named the Allam Cycle, after lead inventor Rodney Allam. Unlike traditional carbon capture technologies, the NET Power cycle inherently produces pipeline-ready CO2 for sequestration or use in enhanced oil recovery (EOR) without reducing plant efficiency or increasing costs. EOR is a decades-old technology that uses carbon dioxide to extract stranded oil from mature oil fields while sequestering carbon dioxide below ground.
The system provides methods for power generation using a high efficiency combustor (e.g., a transpiration cooled combustor) in combination with the circulating fluid (e.g., CO2 circulating fluid). The CO2 circulating fluid can be introduced into the combustor along with a fuel and an oxidant for combustion such that a high pressure, high temperature fluid stream is produced comprising the circulating fluid and combustion products. The fluid stream can be introduced into a turbine. The circulating fluid (at least a portion of which may be recycled from the fluid stream) can be passed through the same heat exchanger to heat the circulating fluid prior to introduction into the combustor.
Pure CO2 for sequestration
The system can produce substantially pure CO2 at pipeline pressure for sequestration. The CO2 also may be recycled into the power production system. A wide variety of fuel sources can be used. For example, it can make use of gaseous (e.g., natural gas or coal derived gases), liquid (e.g., hydrocarbons, bitumen) and solid (e.g., coal, lignite, pet-coke) fuels.
The US Department of Energy estimates that nearly 84 billion barrels of oil are recoverable using EOR in the US and 500 billion to 1 trillion barrels are recoverable worldwide. However, current sources of CO2 for EOR are only meeting a small fraction of that need, as most industrial CO2 capture technologies cannot produce cost-effective, EOR-ready CO2. NET Power’s technology will have both the capacity and economics to enable the EOR industry to unlock this vast resource while simultaneously sequestering large quantities of carbon dioxide
below ground.
Under the current program, Shaw, Toshiba, Exelon and NET Power will develop a 25MW NET Power natural gas plant that is expected to begin operating in mid-2014. Construction of the first 250MW plant is expected to begin in late 2014 or early 2015. NET Power will be responsible for overall project development and systems engineering; Toshiba will design, test and manufacture a combustor and turbine for the NET Power system; Shaw will provide engineering, procurement, and construction services; and Exelon will support the development and operations of the 25MW plant by selecting the site, obtaining permits and commissioning the facility. Shaw will also provide up to $50.4 million in cash and in-kind services.
