Slashdot Mirror
First US Offshore Wind Farm To Usher In New Era For Industry (ap.org)
An anonymous reader quotes a report from Associated Press: The nation's first offshore wind farm is set to open off the coast of Rhode Island this fall, ushering in a new era in the U.S. for the industry. Developers, federal regulators and industry experts say the opening will move the U.S. industry from a theory to reality, paving the way for the construction of many more wind farms that will eventually provide power for many Americans. Deepwater Wind is building a five-turbine wind farm off Block Island, Rhode Island to power about 17,000 homes. The project costs about $300 million, according to the company. CEO Jeffrey Grybowski said the Block Island wind farm enables larger projects because it proves that wind farms can be built along the nation's coast. Offshore wind farms, which benefit from strong winds because of their location, are being proposed near population epicenters that lack the space to build on land. Indeed, several states are pushing ambitious clean energy goals, which include offshore wind. Among them is California, which has a target of generating 50 percent of its power from renewable sources by 2030. Vermont hopes to hit 55 percent by next year and Hawaii has called for 100 percent renewable power by 2045.
As a former marine engineer I have doubts. Unless materials science has changed dramatically, things do not thrive in ocean environments. Those materials that last longest tend to be very expensive. Maintenance on land based windmills is expensive and dangerous ... out there it will be a serious problem.
...omphaloskepsis often...
it will take 16.96 years to pay that $300 million back.
That is about a 6% ROI, at a time when banks get 3.5% on 30 year mortgages. Seems like a good investment to me.
Meanwhile, in England, Theresa May just semi-canceled the Hinkley Point nuclear project because the falling price of wind energy was making new nukes uncompetitive.
Building anything to handle a 100% salt spray exposure dramatically increases the cost. Have a boat on a lake? Takes some maintenance. Have the same boat on the ocean/saltwater harbor and required maintenance skyrockets. Saltwater is incredibly corrosive. What works in fresh water will quickly die in saltwater (even stainless steel will corrode away in saltwater). Add in parts that have full 360 degree spins so open bearing races (sure, lubricated - but still open) and you're asking for a lot of trouble.
On land, you can use a lot of materials that simply will not hold up to constant salt spray exposure (like aluminum).
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
you'll make profit only for the last 3 years of the 20 year lifespan.
The "max 20 year lifespan" is something that Ravenshrike (the GPP) pulled out of his butt. There are offshore turbines in Denmark that already exceed that, and we have learned a lot about building offshore turbines since then. For instance, modern turbines are much bigger and installed much higher above the water than they were 25 years ago. These turbines will stand more than 100 meters above the sea. There is very little salt spray up that high. They will likely be active for much longer than 20 years.
So how long do they last? You castigate Ravenshrike for pulling things out of his butt, but you do the same and say they will be active for much longer than 20 years.
Additionally, direct spray isn't needed to corrode your metal. Ask anyone who lives near the ocean - direct exposure isn't needed, and most salt spray/salt fog tests do not need to directly spray saltwater at the object - just high salt content moisture in the air is damaging.
Lastly, given that Denmark has extremely high power rates (about 3X that in the US), perhaps they are the perfect example of why offshore wind is not really a good bet - the power generated is very expensive due to very high maintenance costs. What I see is that offshore wind maintenance costs are on par with the TOTAL cost of electricity for much of the US. Just maintenance alone costs more than the entire cost of power generation. That's not a good sign...
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
It's slashdot not talk radio so how about numbers in megawatts instead of "enough to power X homes" or volkswagens per libraries of congress or similar utterly useless descriptions?
Part of the $300M is for building a grid to carry the electricity back to shore. This is a fixed cost for most wind farms. It doesn't matter if you have one turbine or 25 you are still going to have to build that connection in order to send the electricity back. So the more turbines you have in your farm the better you can spread this cost out per turbine.
Note that each turbine will have a cost associated with connecting it to the to the grid that makes up the wind farm. The more turbines that you have in the farm the larger this grid is and the more it will cost to connect them together. But the turbines are always going to be much closer together than they are from the shore so the cost to connect the turbines is going to be smaller than connecting the farm to the shore.
Wind turbines are getting larger all the time and when they get larger they get more expensive. However as the length, n, increases the power available goes up as a function of the area swept by the blades, n^2. Of course nobody is doubling the blade length but we are seeing turbines of 5MW and more where a few years ago it was 4MW. So yes the turbines are getting more expensive but that's because they are able to generate more electricity.
I've seen the future of wind farms, at the southern tip of Hawaii, in the plains of California... after fifteen to twenty years of playing with the toys they all end up as decaying eyesores once people realize they cost a lot more than they give back in power.
The problem here is that the technology of wind turbines changes. And one of the things that is changing is how much maintenance a wind turbine needs. For example, this link claims that average annual maintenance costs as a fraction of initial investment has gone from 3% for "older" wind turbines over their lifespan to 1.5-2% for current generation.