A group of farmers looks over a field of cassava in Mbinga, Tanzania, in 2016; unearthed cassava root is pictured (Inset). Researchers in the Cassava Virus Action Group have been able to increase yield by using portable DNA sequencers and extractors that facilitate the early detection of diseased plants. Image credit: Laura Boykin (photographer).
Plant Design Suite 2019 Portable
Download Zip: https://gohhs.com/2vIivA
Henrik Krehenwinkel, Aaron Pomerantz, James B Henderson, Susan R Kennedy, Jun Ying Lim, Varun Swamy, Juan Diego Shoobridge, Natalie Graham, Nipam H Patel, Rosemary G Gillespie, Stefan Prost, Nanopore sequencing of long ribosomal DNA amplicons enables portable and simple biodiversity assessments with high phylogenetic resolution across broad taxonomic scale, GigaScience, Volume 8, Issue 5, May 2019, giz006,
Generally, modern small reactors for power generation, and especially SMRs, are expected to have greater simplicity of design, economy of series production largely in factories, short construction times, and reduced siting costs. Most are also designed for a high level of passive or inherent safety in the event of malfunctionc. Also many are designed to be emplaced below ground level, giving a high resistance to terrorist threats. A 2010 report by a special committee convened by the American Nuclear Society showed that many safety provisions necessary, or at least prudent, in large reactors are not necessary in the small designs forthcoming. This is largely due to their higher surface area to volume (and core heat) ratio compared with large units. It means that a lot of the engineering for safety including heat removal in large reactors is not needed in the small reactorsd. Since small reactors are envisaged as replacing fossil fuel plants in many situations, the emergency planning zone required is designed to be no more than about 300 m radius. The combined tables from this report are appended, along with notes of some early small water-, gas-, and liquid metal-cooled reactors.
The US Nuclear Regulatory Commission (NRC) has released a draft white paper on its strategy for reviewing licensing applications for advanced non-light water reactor technologies. The NRC said it expects to finalize the draft paper by November, with submission of the first non-LWR application expected by December 2019. By mid-2019 the NRC had been formally notified by six reactor designers of their intention to seek design approval. These included three MSRs, one HTR, one FNR, and the Westinghouse eVinci heatpipe reactor. In December 2019 the Canadian Nuclear Safety Commission (CNSC) and the US NRC selected Terrestrial Energy's Integral Molten Salt Reactor (IMSR) for the first joint technical review of an advanced, non-light water nuclear reactor.
In May 2020 the DOE launched the Advanced Reactor Demonstration Program (ARDP) offering funds, initially $160 million, on a cost-share basis for the construction of two advanced reactors that could be operational within seven years. The ARDP will concentrate resources on designs that are "affordable" to build and operate. The programme would also extend to risk reduction for future demonstrations, and include support under the Advanced Reactor Concepts 2020 pathway for innovative and diverse designs with the potential to be commercial in the mid-2030s. Testing and assessing advanced technologies would be carried out at the Idaho National Laboratory's National Reactor Innovation Center (NRIC). The NRIC started up in August 2019 as part of the DOE's Gateway for Accelerated Innovation in Nuclear (GAIN) initiative, which aims to accelerate the development and commercialization of advanced nuclear technologies. In October 2020 grants of $80 million each were made to TerraPower and X-energy to build demonstration plants that can be operational within seven years.
In November 2021 the UK government announced that it would contribute 210 million in grant funding to Rolls-Royce SMR to match private investment in this venture. Rolls-Royce Group, BNF Resources UK and Exelon Generation will invest 195 million over about three years in it. Rolls-Royce said the SMR business, which will continue to seek further investment, will now "proceed rapidly with a range of parallel delivery activities, including entry to the UK generic design assessment (GDA) process and identifying sites for the factories which will manufacture the modules that enable onsite assembly of the power plants." The reactor is designed for hydrogen and synthetic fuel manufacturing as well as electricity generation. The Rolls-Royce SMR consortium, involving many of the major UK engineering firms, aims to build 16 reactors, each a pressurized water type of 470 MWe.
In November 2019 CNL announced that Kairos Power, Moltex Canada, Terrestrial Energy and Ultra Safe Nuclear Corporation (USNC) had been selected as the first recipients of support under its Canadian Nuclear Research Initiative (CNRI). This is designed to accelerate SMR deployment by enabling research and development on particular projects and connecting global vendors of SMR technology with the facilities and expertise within Canada's national nuclear laboratories. Recipients are expected to match the value contributed by CNL either in monetary or in-kind contributions.
In December 2019 CEZ in the Czech Republic said it was focusing on 11 SMR designs including these seven: Rosatom's RITM-200, GE Hitachi Nuclear Energy's BWRX-300, NuScale Power's SMR, China National Nuclear Corporation's ACP100, Argentina's CAREM, the South Korean SMART, and Holtec International's SMR-160.
About five decades ago the US Army built eight reactors, five of them portable or mobile. PM1 successfully powered a remote air/missile defence radar station on a mountain top near Sundance, Wyoming for six years to 1968, providing 1 MWe. At Camp Century in northern Greenland the 10 MWt, 1.56 MWe plus 1.05 GJ/hr PM-2A was assembled from prefabricated components, and ran from 1960-64 on high-enriched uranium fuel. Another was the 9 MWt, 1.5 MWe (net) PM-3A reactor which operated at McMurdo Sound in Antarctica from 1962-72, generating a total of 78 million kWh and providing heat. It used high-enriched uranium fuel and was refuelled once, in 1970. MH-1A was the first floating nuclear power plant operating in the Panama Canal Zone from 1968-77 on a converted Liberty ship. It had a 45 MWt/10 MWe (net) single-loop PWR which used low-enriched uranium (4-7%). It used 541 kg of U-235 over ten years and provided power for nine years at 54% capacity factor.
ML-1 was a smaller and more innovative 0.3 MWe mobile power plant with a water-moderated HTR using pressurized nitrogen at 650C to drive a Brayton closed cycle gas turbine. It used HEU in a cluster of 19 pins, the core being 56 cm high and 56 cm diameter. It was tested over 1962-66 in Idaho. It was about the size of a standard shipping container and was truck-mobile and air-transportable, with 12-hour set-up. The control unit was separate, to be located 150 m away.
A 2018 report from the US Army analysed the potential benefits and challenges of mobile nuclear power plants (MNPPs) with very small modular reactor (vSMR) technology. This followed a 2016 report on Energy Systems for Forward/Remote Operating Bases. The purpose is to reduce supply vulnerabilities and operating costs while providing a sustainable option for reducing petroleum demand and consequent vulnerability. MNPPs would be portable by truck or large aircraft and if abroad, returned to the USA for refuelling after 10-20 years. They would load-follow and run on low-enriched uranium (
Since 2010 Sosny has been involved with Luch Scientific Production Association (SRI SIA Luch) and Russia's N.A. Dollezhal Research and Development Institute of Power Engineering (NIKIET or RDIPE) to design a small transportable nuclear reactor. The new design will be an HTR concept similar to Pamir but about 2.5 MWe.
In 2015 it was reported that the Russian defence ministry had commissioned the development of small mobile nuclear power plants for military installations in the Arctic. A pilot project being undertaken by Innovation Projects Engineering Company (IPEC) is a mobile low-power nuclear unit to be mounted on a large truck, tracked vehicle or a sledged platform. Production models will need to be capable of being transported by military cargo jets and heavy cargo helicopters, such as the Mil Mi-26. They need to be fully autonomous and designed for years-long operation without refuelling, with a small number of personnel, and remote control centre. It is assumed but not confirmed that these reactors will be the MTSPNR.
Although the reactor core is normally cooled by forced circulation (four-loop), the design relies on convection for emergency cooling. Fuel is uranium aluminium silicide with enrichment levels of 18.6%, giving three-year refuelling intervals. A variant of this is the KLT-20, specifically designed for floating nuclear plants. It is a two-loop version with the same enrichment but with a ten-year refuelling interval.
The first floating nuclear power plant, the Akademik Lomonosov, commenced construction in 2007, and was grid connected at Pevek in December 2019. (See also Floating nuclear power plants section in the information page on Nuclear Power in Russia.)
The RITM series is Russia's 'flagship' SMR design. The compact RITM-200M will replace the KLT reactors to serve in floating nuclear power plants, or optimized floating power units (OFPUs) as they are now called by OKBM. It is derived from the OKBM Afrikantov's RITM-200 reactor units in the LK-60 icebreakers and is an integral 175 MWt/50 MWe PWR with 12 steam generator cassettes inside the pressure vessel and four coolant loops with external main circulation pumps. It has inherent safety features, using low-enriched (
In December 2019 NuScale submitted its 60 MWe (now 77 MWe) SMR design to the Canadian Nuclear Safety Commission (CNSC) for pre-licensing vendor design review. Phase 2 of this commenced in January 2020.
B&W Nuclear Energy Inc set up B&W Modular Nuclear Energy LLC (now BWXT mPower Inc) to market the design, in collaboration with Bechtel which joined the project as a 10% equity partner to design, license and deploy it. The company expects both design certification and construction permit in 2018, and commercial operation of the first two units in 2022. Overnight cost for a twin-unit plant was put by B&W at about $5000/kW. 2ff7e9595c
Commentaires