XPost: misc.survivalism, alt.conspiracy   
   From: DB@cocks.net   
      
   On 5/1/2025 11:34 PM, Jan Panteltje wrote:   
   >> Story by Capell Aris The Telegraph   
   >>   
   >> Last Monday, the Iberian grid suffered a disturbance in the south-west   
   >> at 12:33. In 3.5 seconds this worsened and the interconnection to France   
   >> disconnected. All renewable generation then went off-line, followed by   
   >> disconnection of all rotating generation plant. The Iberian blackout was   
   >> complete within a few seconds.   
   >>   
   >> At the time the grid was producing 28.4 GW of power, of which 79 per   
   >> cent was solar and wind. This was a problematic situation as solar and   
   >> wind plants have another, not widely known, downside – one quite apart   
   >>from their intermittency and expense.   
   >>   
   >> This is the fact that they do not supply any inertia to the grid.   
   >> Thermal powerplants – coal, gas, nuclear, for example – drive large   
   >> spinning generators which are directly, synchronously connected to the   
   >> grid. If there are changes which cause a difference between demand and   
   >> supply, the generators will start to spin faster or slower: but their   
   >> inertia resists this process, meaning that the frequency of the   
   >> alternating current in the grid changes only slowly. There is time for   
   >> the grid managers to act, matching supply to demand and keeping the grid   
   >> frequency within limits.   
   >>   
   >> This is vital because all grids must supply power at a steady frequency   
   >> so that electrical appliances work properly and safely. Deviations from   
   >> the standard grid frequency can cause damage to equipment and other   
   >> problems: in practice what happens quite rapidly when frequency changes   
   >> significantly is that grid machinery trips out to prevent these issues   
   >> and grids go down.   
   >>   
   >> When a grid has very little inertia in it – as with the Iberian one on   
   >> Monday – a problem which a high-inertia grid would easily resist can   
   >> cause a blackout within seconds. Lack of inertia was almost certainly   
   >> the primary cause of the Iberian blackout, as Matt Oliver has opined in   
   >> these pages. A grid with more inertia would not have collapsed as   
   >> quickly, and its operators would have had time to keep it up and running.   
   >>   
   >> Restoration of supplies was completed by early Tuesday morning, based on   
   >> reconnection to France, which facilitated progressive area reconnections   
   >> across Spain and Portugal.   
   >>   
   >> Iberia is part of the Continental Europe Synchronous Area which   
   >> stretches to 32 countries. It is interconnected as a phase-locked, 50 Hz   
   >> grid with a generation capacity of 700 GW. To improve the stability of   
   >> this grid, the EU aim is that all partners will extract 10 per cent of   
   >> their power consumption from synchronous interconnectors – ones which   
   >> transmit grid inertia – helping to make the whole system more resilient.   
   >> France is at 10 per cent, but peninsula grids and those at the   
   >> geographical fringe are the least interconnected. Spain has just 2 per   
   >> cent from synchronous interconnectors.   
   >>   
   >> But there are places where things are worse. The UK and Ireland are   
   >> island grids. They do have undersea power interconnectors to Europe but   
   >> these are non-synchronous DC links and transmit no grid inertia. There’s   
   >> little prospect that this will change.   
   >>   
   >> Both the Irish and UK grid system operators had developed an array of   
   >> grid protection services that can control grid frequency, loss of load   
   >> or generation protection, grid phase angle and recovering from grid   
   >> outages. Neither country has, to date, ever experienced a total system   
   >> failure, even during WWII.   
   >>   
   >> In 1974 construction started on Dinorwig Power Station. It is a pumped   
   >> storage generation plant designed specifically for the provision of all   
   >> the UK’s grid protection services. Dinorwig can make huge changes to its   
   >> output in a matter of seconds, compensating for sudden events. Operation   
   >> began in 1984. In 1990 all the UK’s generating stations could provide   
   >> inertia.   
   >>   
   >> Nowadays, 55 per cent of our generation mix (wind, solar, DC imports)   
   >> cannot supply inertia to the grid. Are we approaching a system that   
   >> compares with Spain and Portugal on Monday?   
   >>   
   >> It certainly looks that way. In 2012 the National Grid produced a solar   
   >> briefing note for the government which is still available online. In   
   >> that note they imagine a system that has 22 GW of solar power attached   
   >> to the grid. They demonstrate their concerns based on a sunny summer day   
   >> when demand is low. The sun rises at 5 o’clock when little or no   
   >> synchronous plant other than nuclear generation will be on line and at   
   >> midday, solar is 60 per cent of all generation. The Grid’s engineers   
   >> then considered that situation “difficult to manage” and concluded that   
   >> wind+solar power must never exceed 60 per cent of generation.   
   >>   
   >> We now have 17.7 GW of grid-connected solar farms to which we must add   
   >> all rooftop solar installations. At midday on Tuesday according to   
   >> Gridwatch the UK’s asynchronous, no-inertia generation was at 66 per   
   >> cent of total generation.   
   >>   
   >> In 2014 National Grid produced a System Operability Framework document.   
   >> Their objective was to outline how future scenarios of generation mixes   
   >> would impact upon protection services for the grid. As more and more   
   >> renewable generators are brought on-line, the difficulties of managing   
   >> the grid have become more and more onerous. For example, one service   
   >> titled “primary response” in 1990 called for selected generation plants   
   >> to increase generation within 10 seconds after a fault is detected: by   
   >> 1,200 MW in winter and 1,500 MW in summer. In 2024 these increases are   
   >> required in 1.2 seconds!   
   >>   
   >> After nearly 50 years of operation, Dinorwig Power Station is currently   
   >> shut down for major repairs and there has been no information on when it   
   >> will re-open. Over the next five years all of our nuclear stations, bar   
   >> Sizewell, will be closed. Over the same period our combined cycle gas   
   >> generator fleet will halve from 30 GW to 15 GW. (It takes 5 years to   
   >> build a new CCGT even using an existing site. The new ones are 66 per   
   >> cent efficient and cost less than £1 billion to build a 1 GW plant – one   
   >> third the cost of an offshore windmill.)   
   >>   
   >> We will lose huge amounts of grid inertia. Low-inertia operation will   
   >> become routine. It is hard to imagine that we won’t start to suffer   
      
   [continued in next message]   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)