From http://www.vestas.com/en/media/news/news-display.aspx?action=3&NewsID=3153
- an advertisement for the new Low Wind Speed Turbine from Vestas, one of two such turbines (the other from REPower) introduced at the 2012 Husum Wind Energy Fair.
It's a strange time in the wind biz. The US wind turbine industry is imploding back to hibernation mode as the cliff of the end of the Production Tax Credit (PTC) on Dec 31 of this year gets closer and closer. For example, last week Siemens laid off over 600 people at one of its American factories that were recently built due to the fall-off in sales for next year. Meantime, the American Wind Energy Association (AWEA) struggles in vain to get a PTC extension bill passed in some form. But even though a majority of House members would pass it, no such chance is given by the lock step Republican House leadership opposition to allowing the wind industry to exist anymore in this country in any respectable scale. Talk about a gift to Europe, Canada and China.... Well, there are lots of reasons/excuses for the acts of these House Republicans, but deep down, threats from wind turbines to the ability of the natural gas, coal and nuke industry to extract outrageous rentier profits from their old fully depreciated generation units are now recognized (no such threat of significance comes from solar PV), and evidently these won't be tolerated any more. At least until the Presidential election happens in early November. The inability of facts to have any effect on Republicans is a fact that AWEA - which goes to great lengths to be neither Democratic or Republican but instead pro-wind energy - is having a really hard time with... Maybe they never got the memo from the Romney campaign as well as the Republican establishment and its billionaire funders such as the Koch brothers (Neil Newhouse is a senior Romney campaign worker/manager):
Meanwhile, some parts of Europe are also imploding with "Austerity", notably Portugal, Spain and Greece. The once vibrant wind industry in Spain is having a hard time, and the new conservative government is seriously taking steps to cripple the wind energy industry in Spain (pre--Austerity it directly employed 30,000 people in Spain - equivalent to ~ 200,000 people in the US). Furthermore, just about all economic demand is shrinking at an accelerating rate, as unemployed people do not have the money to purchase stuff and thus keep the economy moving along. In the last year, Euro 224 BILLION (20% of Spain's yearly GDP!!!) in funds from Spanish banks has been moved to other parts of the world, notably Germany, where people and companies now have to pay banks to keep their money (see http://www.nakedcapitalism.com/2012/09/wolf-richter-catalonia-cries-for-independence-while-the-spanish-military-threatens-to-crush-the-vultures.html). Bank runs are not good for countries with 20% overall unemployment rates and more than 50% unemployment among people under 30. Spain now gets around 16% of its electricity from wind, and on occasion (windy times) over half of all electricity used in Spain comes from wind turbines (see http://www.aeeolica.org/en/about-wind-energy/wind-energy-in-spain/). An example of killing the gooses laying those golden eggs...
And yet, here comes the new models of wind turbines. Last year, new Low Wind Speed Turbines (LWST) in the 100 to 117 meter range were introduced en masse to the market, with great success. Now comes the 120 or more meter rotor diameter systems coupled to taller towers, which are sort of mandatory for big rotor diameters. The taller towers are often accomplished by the use of hybrid towers - the lower section is made of reinforced concrete sections that are pieced together on site, and then the top section is steel. For example, the 120 meter tower used by Nordex for their existing N117 unit (2.4 MW, 117 meter rotor diameter) has a 60 meter tall concrete section onto which are added 60 meters (often in 3 parts) of steel tower. Or for Enercon, tall towers (135 meters) can be entirely made of reinforced concrete, and often are. These taller towers have to be more rigid than shorter ones, and to do these in all steel requires incredibly thick lower steel sections; all that steel also costs a fortune. The manufacture of longer, slimmer blades which are quieter and more aerodynamically efficient is also important. These blades are flexible and one of the reasons that towers must be made more rigid is so the vibrations of the tower and blade don't add to each other and cause the blade to smash into the tower. Lighter weight blades are also even more important, because the stresses on the tower are a function of the weight at the top of the tower. Lighter blades with greater rigidity have been achieved most by improving their internal designs.
And then there are manufacturing cost considerations. Lighter weight blades means less resin, which is the bulk of the mass of the blade, and getting more expensive as petroleum rises in price (resins are often made with Bisphenol A epoxy materials, and BPA is made from benzene and propylene, which are often made from crude oil). Incorporating more of the stronger but more expensive carbon fiber instead of glass fiber can also help minimize blade mass, but this is a very competitive industry, so costs can't go up much at all.
Getting more energy out of a turbine at less cost generally means making the rotors bigger and towers taller, and maybe the generators bigger, but not always. But if you get more energy out for a little bit more investment (more energy out per unit investment in), you're going in the right direction. Since a lot of the soft costs (permitting, wind evaluation, grid connection) and some of the construction costs (crane rental, electrical work, substation, parts transportation and even the foundation) cost about the same for a bigger turbine as a slightly smaller one, economics dictate that lower cost energy production comes from bigger turbines. And for a given location, taller towers tap faster winds. And a bigger rotor intercepts more moving air, which is how electricity gets made. But all this is easier said than done....
There is also a push to get the "net yields" up from the 25% to 35% range (older models with small rotor diameter to generator ratios) to near 50%. In a recent "mini-farm" in Finland, Nordex has quoted a 52% net output for its N117 on a 120 meter tower for a site with 7.5 m/s winds at 120 meters height. If this works out, the final order for this area would be worth around $US 700 million....
So far, the Gamesa 2 MW G114 turbine seems to be the one "most attuned" to low wind speed conditions. They claim a 20% annual energy output increase versus their G97 model in suitable winds, which itself was targeted at moderate wind speeds. This one comes with tower heights of 93 meters (steel) 120 and 140 meters hybrid towers... It was also supposed to be made in Pennsylvania next year, but due to the end of the PTC, that might not happen for a while. Turbines such as this one could be quite the "game-changer" in the Southeast and Northeast parts of the US, allowing about 25% more of the continental US to be considered as having "commercial grade winds". Could be, but "could be" also might be "no way", too...
For the Husum event (41,000 visitors, which is pretty good for an industrial exhibitions...), the newbies of note are the Vestas V126 x 3 MW and the REPower M122 x 3 MW. For the time being, these are only intended to be made and sold in Europe, but for those with sufficient money, they will make them/sell them wherever it is profitable... After all, Vestas and RE Power are corporations making and selling these turbines, not charities.... But, given the lack of motivation in the US to install wind turbines at a rate sufficient to make a difference in our economy or rate at which we are trashing the planetary climate control system, well, no use holding your breath....
Anyway, just a bit of a tease. Based on preliminary information, a site with a 6.25 m/s wind at 80 meters in a forest-like area (roughness length = 1 meter) - quite typical for NY State - would get close to a 39.2 % net output before things like array losses are considered for the V126 on a 119 meter tower. For a V100 x 1.8 MW on an 80 meter tall tower, a net output of "only" 36.4% at this same location would result. And while this only seems like a minor difference in efficiency, the V126 would kick out an average of 1178 kw while the V100 would average 665 kw.... That's about 77% more energy from a given site. No wonder a Vestas rep estimated the possible sales in Europe of these new LWST at over 22 GW (or about $US 55 billion in the next few years). That's quite a lot, given that the V126's "smaller cousin", the 3 MW V112, just had it's 1000th unit sold (in less than 2 years). And again, while this may not seem like much, that's around $US 6 billion in sales... BTW, 72 of the V112's are almost all installed at the Marble River wind farm in northern NY...
As for the REPower approach, their 3.0M122 unit comes with a 139 meter tall tower system, which taps winds that are slightly faster than those that exist at 119, 93 or 80 meters above the ground. Using the same conditions (6.25 m/s at 80 meters height) in a Buffalo, NY like setting, average power production would be around 1266 kw, or a 42.2% net output. This is because winds are slightly faster at 139 meters (7.03 m/s) versus 119 meters (6.82 m/s), and the smaller blade rotor of the M122 system can overcome the advantage of a larger rotor blade for the V126. Of course, the big question is how much does that taller tower cost, and is it worth it compared to the bigger blade shorter tower option form Vestas... But, unless we in the US don't start reaching for excellence in wind energy production that allows for a lot of "low wind" opportunities (great for local grid enhancement and enhanced local economic viability), it won't matter. Even though there are companies in the US capable of making such concrete towers and who have advertised such products. So far, only one of them has been/is being installed in the US, in this case on an Acconia 3 MW by 116 m rotor unit in an Iowa demonstration project.










