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Why ‘Clean Coal’ Remains out of Reach

first_imgWhy ‘Clean Coal’ Remains out of Reach FacebookTwitterLinkedInEmailPrint分享Robert Rapier for Forbes:Since the coal industry and utilities that use coal want to continue to exist, they have pushed the clean coal narrative for many years. After all, if there is some hope that this dream is achieved, perhaps the EPA could cut them some slack while they work out the kinks.It’s not so hard to imagine how it would be done. In fact, it’s already been demonstrated many times at a pilot scale. The exhaust from the power plant stack is captured, compressed, and stored underground — either in a cavern or an old oil or gas field.The key challenge has always been one of economics. The capital cost of capturing and compressing those emissions is very high, and the power consumed in compressing the carbon dioxide places a parasitic load on the power plant. Just to compress the emissions can require the electric power requirements of 10% of the plant output, and then it must still be transported to an appropriate site and pumped into the ground. All of these factors drive up the costs to the point that coal power with carbon capture is prohibitively expensive relative to competing ways of producing power.The prohibitive costs are amply demonstrated by the FutureGen project in Illinois. This project was a partnership between the United States Department of Energy (DOE) and an alliance of coal mining and electric utility companies. The project was to be located at the 275 MW Meredosia Power Station in Illinois.FutureGen won $1.1 billion in federal money in 2009, and the project cost was estimated to be $1.65 billion. The DOE spent $202 million on the project, but missed project deadlines and unresolved technology challenges ultimately caused the DOE to pull the plug on the project in 2015.While there are a number of other pilot projects underway around the world, they all suffer from the same basic problem. The costs of competing technologies are close enough to coal that when you try to capture the carbon dioxide emissions it pushes the cost of coal-fired power beyond the competition.Thus, in reality there aren’t any commercial clean coal technologies. It’s very likely there won’t be any. So for countries that have committed to reducing carbon emissions, the pressure to phase out coal will continue to be intense.Full item: The Elusive Search For Clean Coallast_img read more

UCL: Spurs stun Man City in quarter final second leg

first_imgTottenham overcame Manchester City in a classic encounter at Etihad Stadium to reach the last four of the Champions League for the first time.Fernando Llorente’s goal, bundled in from a corner and confirmed by VAR 17 minutes from time, gave Mauricio Pochettino’s side victory on away goals on a night of tension, attacking quality and defensive frailty that ended City and Pep Guardiola’s quest for a historic quadruple of Premier League, Champions League, FA Cup and League Cup.In a game of relentless drama, City even thought they had won it in injury time only for Raheem Sterling’s goal to be ruled out for offside by VAR.Spurs were protecting a 1-0 lead from the first leg but an opening 21 minutes of chaotic brilliance saw City lead 3-2 on the night as both teams exchanged goals at will. 6:52: Son Heung-min’s shot squirms past Ederson Source: BBC Three minutes 51 seconds: Raheem Sterling makes it 1-1 on aggregate Sterling lit the blue touchpaper on a thunderous atmosphere when he curled in a precision finish from the edge of the area after only four minutes, but Spurs responded with a double from Son Heung-min as he took advantage of errors by Aymeric Laporte.Bernardo Silva put Spurs level on the night with a shot that deflected past Hugo Lloris then Sterling arrived on the end of the outstanding Kevin de Bruyne’s cross to score at the far post.It left City effectively needing to win the second half and they looked on course when Sergio Aguero crashed home their fourth after De Bruyne sliced Spurs open before Llorente, on as a first-half substitute for injured Moussa Sissoko, bundled in from a corner via his hip – the goal given after a VAR check for handball.In one last extraordinary twist, City thought they had snatched victory and Sterling a hat-trick, but emotions switched instantly as VAR had the final word once again, ruling that Aguero was in an offside position as Bernardo Silva diverted the ball into his path.Spurs go on to face Ajax at the end of unforgettable encounter that left everyone involved stunned and breathless. 9:02: Son curls into the far corner to put Spurs 3-1 up on aggregate How extraordinary first half unfolded 20:32: Sterling meets Kevin de Bruyne’s cross to make it 3-3 overall 10:43: Bernardo Silva’s deflected effort finds the net for Citylast_img read more