News | Headlines
Russia increases attacks on Ukraine’s energy infrastructure
Ukraine Update
Russian attacks on Ukraine’s energy infrastructure continued throughout December with the UN reporting in mid-month that 50% of the country’s energy infrastructure had been put out of action or destroyed. On 29 December Russia carried out the heaviest bombardment yet, when many regions of Ukraine, including its capital, faced the biggest wave of strikes in weeks targeting national infrastructure. Russia dispatched explosive drones to selected regions overnight before broadening the barrage with “air and sea-based cruise missiles launched from strategic aircraft and ships” in the morning, as reported by the Ukrainian air force. Jaco Cilliers, the resident representative to Ukraine for the UN Development Programme, said Ukrainian president Volodymyr Zelenskyy has asked the UNDP and World Bank to do a ‘needs and damage assessment’ of the infrastructure around the energy grid. The initial report is expected to be ready by the end of January, and is to be updated every two months going forward.
IAEA update
According to the International Atomic Energy Agency’s Update 143, director general Rafael
Grossi updated president Volodymyr Zelensky in Kyiv on 19 January about the expanding and intensifying activities of the IAEA in helping Ukraine ensure nuclear safety and security at its nuclear facilities during the military conflict, with several permanent IAEA expert missions recently established across the country. They also continued their discussions on a proposal by Mr Grossi to set up a nuclear safety and security protection zone around the Zaporizhzhya Nuclear Power Plant. Europe’s largest NPP has repeatedly come under fire in recent months, triggering deepening nuclear safety and security concerns.
The director general stressed that the zone is essential for preventing a severe nuclear accident and said he would press ahead with his efforts to make it happen as soon as possible.
“Everybody agrees that the plant – located on the frontline in an active combat area – needs to be protected, but these are very complex negotiations. I will not stop until the much-needed zone is a reality. I will continue my intensive consultations with both Ukraine and the Russian Federation in the coming days and weeks,” he said.
“This major nuclear power plant continues to face daily dangers. Our team there
continues to hear explosions close to the site” he added.
In Kyiv, the director general also met with prime minister Denys Shmyhal, with whom he had agreed in December to establish permanent IAEA nuclear safety and security expert teams at all of Ukraine’s NPPs and the Chornobyl site.
That plan was implemented during the week of 16 January with IAEA flag-raising ceremonies at the South Ukraine and Rivne NPPs, and the Chornobyl site. Two IAEA experts are now continuously staying at each of these three facilities to provide technical support and assistance, assess the plants’ equipment and other needs and report about the situation to IAEA headquarters and the world. “Across Ukraine – from north to south – this week has seen a major expansion in the IAEA’s on-the-ground support for the country’s efforts to prevent a severe nuclear accident during the war. At Ukraine’s request, the IAEA flag is now flying at these important nuclear facilities. For the first time, we will have our top experts permanently present at all of Ukraine’s nuclear power plants as well as the Chornobyl site. Their vital work will help reduce the very real nuclear dangers the country is facing,” Mr Grossi said.
First horizontal-shaft, six-nozzle Pelton turbine in operation Austria Hydropower
The first horizontal-shaft, six-nozzle Pelton turbine, at the Gerlos 1 pumped storage power plant in Austria, has run successfully, for over two months, it is reported, and is “setting new benchmarks.” In the Pelton turbine, which is especially suited to plants with high heads, the water is directed by forming free jets at very high velocity from one or several nozzles to the Pelton runner. Until now, Pelton turbines with more than three nozzles have always been designed with a vertical shaft. The main reason for this was that it allowed higher efficiency than a horizontal arrangement. Voith Hydro has now successfully eliminated this drawback, as demonstrated in the Gerlos 1 power plant, where for the first time, an efficiency level comparable to that of the vertical-shaft configuration has been achieved. The plant’s existing four vertical-shaft Pelton turbines were successfully replaced by one six-nozzle horizontal-shaft Pelton wheel. In addition to this application, the technology is of particular interest for upgrades of existing hydropower plants
where single- or double-nozzle horizontal- shaft units are already installed. This is because the turbine can be replaced without major structural works, which significantly reduces civil costs and installation times. At the same time, there is enormous potential for increasing efficiency, says Voith. The associated potential reduction in the number of turbines is also said to lower future maintenance costs. The new development requires less excavation and is more compact with a smaller footprint than conventional solutions. This is also associated with a shorter installation time, which reduces the overall investment costs. The interaction between the water jet and the buckets of the Pelton wheel is extremely brief, often just a few milliseconds. This is why the flow simulation of Pelton turbines is by far the most complex and difficult of all hydro turbomachinery simulations. Voith Hydro has refined the methods in recent years such that the housing flow can now also be analysed. This important advance has also made a significant contribution to the development of the new concept.
Flow simulation for the horizontal-shaft Pelton turbine
4 | January/February 2023 |
www.modernpowersystems.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45
