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Sept 8th 2018
World's Largest Offshore Wind Farm Opens in Irish Sea
The world's largest offshore wind farm opened in the Irish Sea on Thursday, covering an area of 145 square kilometers (55 square miles).
The 659-megawatt Walney Extension, located approximately 19 kilometers (12 miles) off the coast of Cumbria, England, consists of 87 turbines and is capable of generating enough renewable energy to power almost 600,000 UK homes.
To compare, the 175-turbine London Array—now the second largest offshore wind farm in the world—has a 630-megawatt capacity, or enough to power about half a million homes.
The Walney Extension is run by Danish energy giant Ørsted (formerly Dong Energy) and the Danish pension funds PKA and PFA.
The project was constructed on time and within budget, Ørsted UK managing director Matthew Wright said in a press release.
The wind farm features 40 MHI Vestas 8-megawatt turbines and 47 Siemens Gamesa 7-megawatt turbines, the first project to use wind turbines from two different manufacturers. That's less than half the number of turbines used at the London Array, but Walney's turbines are more powerful.
"It's another benchmark in terms of the scale. This—bigger turbines, with fewer positions and a bit further out—is really the shape of projects going forward," Wright told The Guardian.
MHI Vestas turbines stand 195 meters (213 yards) tall, and are the most powerful being used globally.
The UK government approved the Walney Extension contract in 2014 that promised a minimum price of £150 ($195) per megawatt hour for 15 years. Since the contract was awarded, costs of offshore wind plummeted more than 50 percent, with the latest auction dropping as low as £57.50 per megawatt hour,Reuters noted.
Offshore wind technology is advancing at a rapid pace, meaning the Walney Extension could soon lose its title. For instance, Ørsted's Hornsea Project One off the UK's Yorkshire coast is expected to be fully operational by 2020 and will have a capacity of 1,200 megawatts, or enough power for more than one million UK homes.
The Netherlands is also planning a massive offshore wind farm proposed by Dutch electric grid operator TenneT. If that gets the green-light, the 10,000-turbine complex could produce up to 30 gigawatts of power by 2027. That's enough electricity to power a city of 20 million people.
July 2nd 2018
UK heatwave helps solar power to record weekly highs
Britain’s heatwave has helped break several solar power-generation records, and over the weekend the renewable energy source briefly eclipsed gas power stations as the UK’s top source of electricity.
While new solar installations have virtually flatlined over the past year, a run of largely cloudless days has seen a series of highs for power generation by the sector.
Solar broke the record for weekly output between 21 and 28 June, producing 533 gigawatt hours of power.
During that period, solar generated more than 75GWh on five of the seven days, another record. In a first, solar output also hit more than 8GW for eight consecutive days.
A decade ago, solar contributed almost nothing to UK electricity supplies.The records are largely symbolic – gas and nuclear generated much more power in recent days – but the milestones shows how far the technology has come.
For about an hour on Saturday afternoon, solar panels across the country’s rooftops and fields were the number one source of electricity, with a share of more than 27%. So far, solar has only come top at weekends, when demand is lower.
The record for peak solar generation was 9.42GW, set on 14 May this year.
At the end of May, there was a total of 12.8GW of solar capacity in the UK, up just 1.6% on May 2017.
The rate at which solar records are set is likely to slow, as growth has petered out due to subsidy cuts. Incentives for householders to put panels on their roofs are due to expire next year, with no sign of a replacement scheme.
At the bigger scale, some developers believe they can build without subsidies, by going large.
Hive Energy told an industry audience last week that it believes technological improvements mean its planned Kent solar farm will have 14% more capacity than originally conceived.
The Cleve Hill scheme could have a capacity of as much 400MW, the company said, compared to the UK’s current largest solar farm, a 72.2MW one in Wales.
Dr Alastair Buckley, a solar expert at the University of Sheffield, said: “This marks the start of subsidy-free solar being economically viable, and I genuinely believe we’ll see bigger changes to the electricity sector in the next 10 years than we’ve seen in the past 10.”
May 8th 2018
The battle of the gas-sucking mega giants is set to begin
By Chris BaraniukTechnology of Business reporter
Off the coast of Western Australia, a battle between mega giants is unfolding. The combatants involve the world's biggest semi-submersible platform, the longest sub-sea pipeline in the southern hemisphere, and the largest floating facility ever built.
They're all there for the same reason: natural gas - and they're hoping to start drawing it up this month.
As several countries begin to move away from coal as an energy resource, this alternative fossil fuel, which produces 50% less carbon dioxide for every unit of energy generated, is increasingly in demand in our energy hungry world.
Consumption is forecast to rise to 177 trillion cubic feet (tcf) or 5,012 billion cubic metres by 2040, up from 124tcf in 2015, says the US Energy Information Administration.
That's why Shell's gigantic Prelude platform - which is 488m (1,600ft) long and displaces roughly as much water as six aircraft carriers - is competing with Japanese firm Inpex for access to gas in the Browse Basin.
Media captionThe BBC's science editor David Shukman took a look at the Prelude in 2014
Although they are working on separate gas fields, those fields are connected. Shell and Inpex are essentially vying for the same resource.
"The way I describe it - I have a slide I present to clients and I have a picture of two people drinking out of the same milkshake," says Saul Kavonic, an analyst at energy consultancy Wood Mackenzie.
Prelude is a true behemoth.
It has been designed not only to collect gas from sub-sea well heads, but also liquefy it on board at temperatures of -162C.
As a liquid, the gas takes up significantly less space, making it easier to transport around the world on ships. This liquefaction would usually be done after piping the gas onshore, but Prelude can do the job herself - something never achieved on such a scale before.
Some serious technology is involved in making this happen.
Prelude has high-capacity pumps that can draw 50 million litres of water from the sea every hour to help cool down the natural gas. Once liquefied, it is then stored in massive storage tanks with a volume equivalent to 175 Olympic swimming pools.
And this all has to keep going even through the worst imaginable weather. Prelude's hefty mooring chains are designed to survive Category 5 cyclones.
While Inpex has opted for sending its gas onshore for liquefaction, it also has a huge offshore semi-submersible platform to extract water and impurities from the gas first. And nearby, there is a floating storage and off-loading facility called Venturer.
Collectively, Inpex has dubbed these bits of mega-infrastructure Ichthys - ancient Greek for fish.
However, both projects have been beset by delays and spiralling costs, which may be why neither company was prepared to talk to the BBC for this feature.
The pressure to start drawing gas first is obviously intense.
The race for Browse Basin gas has even ignited competition on an international scale. Australia may overtake Qatar to become the world's top exporter of liquefied natural gas (LNG) once Ichthys and Prelude production is in full swing.
But will any future vessel match or even exceed the scale of Prelude?
Mr Kavonic says the fossil fuel industry isn't likely to try to build one any time soon.
"We need new projects to meet demand [for gas] in the early 2020s," he explains. "We needed projects to be sanctioned last year and that didn't happen, we only saw one."
That single project will be built by Italy's oil and gas giant Eni. A floating facility off the coast of Mozambique, it will have a slightly smaller capacity than Prelude - 3.4 million tonnes of LNG per year versus Prelude's 3.6 million. The capacity of Ichthys will be much bigger, at 8.9 million tonnes.
"There's so far no [other] similar projects under the radar," says Jean-Baptiste Dubreuil from the International Energy Agency.
Image copyrightALLSEASImage captionAllseas' Pioneering Spirit twin-hulled vessel can lift an entire oil rig off its legs
The only other comparable vessel might be Allseas' Amazing Grace - an enormous twin-hulled construction ship due to be built over the coming years. Its job will be to lift offshore platforms, however, not process gas.
Without more projects for gas production, industry watchers worry that, in about five years' time, demand for natural gas could outstrip supply.
There is the "spectre of an LNG supply shock in the early 2020s" looming, says Stuart Elliott, gas editor at data provider S&P Global Platts.
The problem could be particularly pronounced in Asia - especially China.
"Last year, Chinese production increased by 8%, but they're not able to keep up with the growth of demand," says Mr Dubreuil. "We expect their needs for imports will grow over time."
In fact, the IEA thinks that China will be importing 43% of its natural gas by 2040. This supply will need to be reliable if the country wants to avoid the gas shortages it experienced last winter - caused, ironically, by a botched attempt to cut coal use.
In the meantime, there is some hope that the unexpectedly speedy growth of renewables - particularly solar and wind - will help to plug the gap.
But there's little doubt that over the next few decades many countries, including the UK, will be heavily reliant on gas for their energy needs.
Prelude and Ichthys are due to come online soon, but neither Shell nor Inpex will commit publicly to a start date.
And with wholesale natural gas prices currently half what they were in early 2014, such multi-billion dollar projects may never recoup their outlay.
As climate change climbs to the top of the world's agenda, funding such huge fossil-fuel extraction projects - impressive feats of engineering as they are - will look increasingly risky.
Both Shell and Inpex must be hoping that their sea-faring mega giants don't go the way of the dinosaurs.
April 11th 2018
World's most powerful wind turbine goes up off Scottish coast
The world's most powerful wind turbine has been successfully installed off the coast of Aberdeen - despite opposition from Donald Trump.
The first of 11 planned superstructures, is so powerful that developers say a single rotation of its blades could power an average UK home for a day.
Before he was elected president, Mr Trump launched a legal challenge opposing the development labelling it “ugly”.
He said the turbines would ruin the view from his multi-million pound golf development at Balmedie and called for the plan to be scrapped.
In a letter to then First Minister Alex Salmond in 2012, the tycoon-turned-Commander-in-chief said: “Don't destroy your coastlines and your countryside with the monstrous turbines. Your country will become a third world wasteland that global investors will avoid."
However, the Scottish Government approved the plans with the UK Supreme Court eventually rejecting Mr Trump’s legal challenge in 2015.
After completing the installation with a giant floating crane, Adam Ezzamel, project manager with Swedish developers Vattenfall said it was a “momentous” moment.
"We are very excited by the cutting-edge technology deployed on all the turbines,” he added.
It is the first time a 8.8 MegaWatt model has ever been deployed commercially. Its 164 metre rotor has a circumference that is larger than that of the London Eye.
And it is hoped the whole 11-structure project – called the European Offshore Wind Deployment Centre – will eventually produce more than 70 per cent of Aberdeen's domestic energy.
Jean Morrison, chair of the the city's Renewable Energy Group, said: “It's a real coup for the region to have the world's most powerful turbines on its doorstep and cements Aberdeen's position as a major global energy city. It also will lead us to a greener future."
Stephanie Conesa, policy manager at Scottish Renewables, said: "Scotland is home to approximately 25 per cent of Europe's offshore wind resource and projects like this promise to harness this potential on a massive scale.
"This ground-breaking facility leads Aberdeen's ongoing transition from fossil fuels to renewables, and reinforces Scotland's global energy status. As the windiest country in Europe with some of the deepest waters, we should be proud of Scotland's burgeoning offshore wind industry.
"With many more promising offshore wind sites on our doorstep, we hope to see similar facilities deployed in Scottish waters in future so we can fully utilise our country's natural resources."
July 25th 2017
Now is the time to check your emergency lighting.
You should always know where you can lay your hands on a small torch.
Remember to keep some matches with your candle's
your mobile phone will give you enough light to move around
Power outage or blackout are terms used to describe when the electricity suddenly goes off, it can happen at any time of the day usually this is part of the distribution grid safety network tripping out, the other reasons for this happening are accidents or weather conditions as a rule, but there are a multitude of other reasons.
Hospitals and Computer Centers where a continuous supply is essential have backup generators that automatically cut in with barely a pause in supply, multistory buildings often used backup generators to maintain their elevators in working order, and there are many other uses for backup generators, in the smaller establishments with elevators people get stuck and cannot even opened the doors.
can be in utter chaos with no traffic lights, and no streetlights, pedestrians
are milling about all over the place as they try to go about their business,
thousands of people marooned in subway trains or out in the country between
train stations, an unusual reason for a power outage is a solar flare which can knock
out the power grids by overloading the circuits.
Because the demand for electricity varies widely throughout the day and there is no means of actually storing electricity on that scale it has to be generated according to the immediate demand, fine tuning of the generation system is usually done by smaller gas turbine generating units which can be switched quickly and remotely.
Another method of backup generation is pumped water storage, at times of low demand stored water is pumped up to another reservoir at a higher elevation, with a sudden increase in demand this water can be released through generating turbines almost instantly to balance the supply and demand.
You can prepare yourself for such an emergency with a little forethought, if possible switch on your mobile phone or your laptop, one of these will give you enough light to find your way to your grab-bag which should contain some emergency lighting, you may be even have some decorative candles which you can light up for this emergency, safety matches are another item that we recommend you put in your grab bag
One of the major problems is the difficulty of storing electricity, but great minds are working on this problem and hopefully they will come to a satisfactory solution, maybe through nanotechnology.
Fortunately with modern communication systems these dangerous situations can be monitored easily and warnings issued by local government, civil defense, police, local radio and television.Home Page - other - blackout