Lots of coastline is plenty windy. Why isn't there more offshore wind generation in USA like there is in other nations? My impression is that rich people who own land on the coast have no taste and think that offshore wind generation is an eyesore.

At least with respect to the west coast:

> Unlike the Atlantic Ocean, where offshore wind farms can be bolted into the seabed in relatively shallow water, the West Coast's continental shelf plunges quickly and steeply.

http://www.latimes.com/business/la-fi-offshore-wind-20160703...

There's a floating wind farm being deployed off Scotland, so this could be possible in the future: http://www.bbc.com/news/business-40699979

Those "floating" wind turbines are still bolted to the seabed (so they don't float away) and are interconnected with wires. They showed how they work via infographics on their website that was on the HN frontpage recently. So the OP's comment about the sloping sea shelf is still relevant.

Not as much as before, because the cost of cable to hold down the turbine is the only thing that gets more expensive with deeper water (the part connecting the floater to the "bolt"). These cables are relatively cheap.

The other option's jackets or monopiles (95% of the market) require almost a 500 kg of steel extra per meter (very rough guideline). This means that at depths more than 25meter the monopile/jacket is more expensive than the wind turbine on top. With the hywind style floaters, this is not the case.

There are efforts underway to develop floating foundations, but I believe it's still in the test phase with only a few turbines deployed.

The first major floating wind farm is being deployed off the coast of Scotland right now!

Yeah, I remembered it as 4 turbines, but it looks like it's 5. So as I said, it's a test farm. But yes, it's real, production-size turbines, not small scale models. I should have clarified that, sorry.

I don't think anyone is going to build a major farm until this one has been running for a couple of years. And they've figured out how to cut costs. Happy to be proven wrong, of course. :)

Statoil isn't the only company working on floating foundations, by the way, although I think they are by far farthest along when it comes to actually putting a big one into production.

For instance, the former CTO of Siemens Wind Power is working on a design. He's going for standard components and as cheap as possible. I wouldn't be surprised to see that in a test production in a couple of years.

edit: Full mea culpa. Parent is right. Keeping this post intact since it still contains green-relevant information and some historical information that may be of interest. Big ups to Scotland for pushing this forward. The Northerners[0] are doing some clever things too like running their own municipal fiber after having their pleas being ignored for ages.

The Danes have been at it for almost the better part of a decade[1]. IIRC, their national transport is 100% green 24/7 and has been for a few years now. They've hit events where 100% of their entire country grid was wind-powered, and are so good at it China[2] brought in Danish consultants for assistance. Here's a real time chart of their energy infrastructure (including exports to Sweden/Norway/Germany)[3].

As a MA native, I remember people on the Cape would joke about the "bridge tax" (i.e., anything coming into the Cape is ~25% more). I know until recently[4] their internet connectivity was horrenduous. Energy there is fairly intermittent as well. Hopefully, they'll pick up a few Siemens units (you can pick up retired Siemens Vestas units on ebay for < 100k that are rated in the 10s of MW!) and deploy a unit or two[6], if only as a PR stunt to make themselves look 'progressive'. A win/win if they can increase employment and bring jobs to the locals in addition to that energy.

--

[0] http://gizmodo.com/5984187/british-farmers-install-their-own... "B4RN" is awesome. It's great to see what a community can get done when they ((apologies in advance:) broad)band together.

[1] https://en.wikipedia.org/wiki/List_of_offshore_wind_farms_in...

[2] http://www.reuters.com/article/us-denmark-windpower-china/ch...

[3] https://en.energinet.dk/#energysystem - Real time chart! Porn for green energy nerds like me.

[4] Thier municipality started to offer gigabit through a peering with the Boston/North Shore providers to position their community as a "business friendly, gigabit ready" region in order to attract more businesses, rather than relying on the traditional tourist-town economy. They brought in some contractors to lay cable from Boston (or likely just North of Boston[5]) which is active now with tons of businesses using it, though I'm not entirely sure if the general populace has FttH.

[5] IIRC Andover or Quincy or somewheres around there (http://nationwidecolocation.com/massachusetts_colocation.htm) was one of the major peering points where a significant amount of NE traffic ran through. Traditionally it has great connectivity first due to all of the DARPA peering that occured around universities (MIT still has the 18.x.x.x class A perma-leased from ARIN). This continued through the late 90s/2000s with Verizon using those DC's as their major peer-points (which is incidentally why FiOS was rolled out so early in the Boston suburbs).

[6] You'd have to deploy them strategically in a region that isn't going to interfere with the yuppies boating experience as they go to the Vineyaahhhd on the 4th. NE has the same NIMBY problem that SF has in that regard.

The significant word was floating.

The Danish offshore windfarms have foundations into the sea bed, like the other British and Dutch ones that have existed for over a decade:

https://en.wikipedia.org/wiki/List_of_offshore_wind_farms_in...

I'm not quite sure about the national transportation being 100% green, or at least I misunderstood what you are saying.

As a Dane I can promise you that our governmental public transport is not 100% green, our main long-distance trains (IC3) currently operate on diesel. Neither is the private transport 100% green, since people can buy traditional combustion engine based cars.

Indeed, only about a quarter of the Danish rail network is electrified -- quite poor when compared to the neighbours. There's a plan to electrify all the main lines by 2025, according to Wikipedia [1]. I'll be pleased when there's no longer an awful smog on the underground platforms at Nørreport.

DSB publish pollution figures for their fleet: https://www.dsb.dk/om-dsb/samfundsansvar/miljo/fakta-om-milj...

[1] https://en.wikipedia.org/wiki/Rail_transport_in_Denmark

MIT gave up half of 18/8 earlier this year, mostly to Amazon - https://www.networkworld.com/article/3191503/internet/mit-se...

They've internally started rolling out IPv4 NAT and IPv6

Not sure if you know, but MA has been trying to build a wind farm off the cape for a decade or more. It's now under contract, but they get sued at every stage, so it's not clear when it will deliver the first watt. Literally everyone is teaming up against wind power off Cape Cod.

https://www.capewind.org

What's the reason for going offshore? Is the wind not as strong on land?

Offshore you can install bigger turbines, because sea transportation of turbine components is not size-limited like rail/road transport. Taller turbines help to reach wind resources that are stronger and steadier. Also, even at the same height, offshore wind resources are often better than they are a few km inland. Finally, offshore wind can supply power to densely populated coastal areas when there isn't room to build turbines on land.

The disadvantages are higher construction and maintenance costs; waves and salt water are much more challenging to materials than the ordinary conditions onshore turbine towers experience.

Perfect answer. Another reason, which kind of joins with the density of the population is the significant noise pollution of larger wind farms.

Great, thank you!

Most cities are on the coast, so offshore offers generation near where it's needed. Doing offshore does not mean ignoring on-shore.

In some cases offshore winds are strong enough that on-shore turbines are less cost effective. That's true for some of the east coast of the US.

"Is the wind not as strong on land?"

Yup !

The turbines are anchored to the sea bed. The wind has a boundary condition against the ground. If the ground is the sea, then the sea current wrt to the sea bed adds to the wind speed wrt to the sea bed.

Therefore, the turbines have zero wind speed only if the wind is blowing exactly against the sea current. Which is hard and rare.

Because the land boundary condition is different, the further away offshore you are, the better the effect is. Also, you might as well pick spots with known stable sea currents.

Fewer issues re land owners. Wind tends to be more steady at sea.

No people complaining about noise, moving shadows and bad aesthetics there.

Offshore wind is considerably more expensive to build, maintain, and interconnect.

This article suggests that offshore wind is 3X as expensive as onshore wind:

http://www.windpowermonthly.com/article/1380738/global-costs...

That puts offshore wind as more expensive than gas turbines, for example. And that's assuming an offshore wind project could get past NIMBY opposition. There's a lot more land in the Midwest than there is coastline.

Without floating foundations, offshore depends a lot on the specifics of the oceanbed. But DONG Energy, which I think is the world biggest developer of offshore wind, recently gave a bid on a subsidy of zero for a farm near Germany. Final investment decision is still in a couple of years so they may pull out of the bid if things don't develop as expected, but not without paying a big fee.

So offshore is expected to get cheaper.

There's a comparison with nuclear down in the thread. I think one important thing to keep in mind here is that these cost reductions coming from industrialization and improved economies of scale are REAL. They happen year over year, has happened for decades, and they will surely lower the price even further in the future. Just like solar. And battery tech for that matter. It's incremental improvements.

Please don't post unsubstantively here.

https://news.ycombinator.com/newsguidelines.html

But what happens if you have a place like the North Sea surrounded by facilities for deploying oil rigs and associated infrastructure, for the oil to run out? There is considerable sunk cost in the infrastructure and with some subsidies to keep yards busy (as such things are needed for national security reasons) it all becomes a lot easier.

What happens is that you get crazy plans like this:

http://cphpost.dk/news/denmark-looking-into-building-north-s...

In a couple of decades, I think the North Sea is going have vast areas full of wind turbines.

One of the only complaints about offshore wind is it "spoils the view". A 250m high turbine can be seen from about 30m away - dogger is twice that distance.

Current plans are for 5GW of production, that's about 15% of the UK's current electricity demand, and more than is produced by the UK's wind farms in total.

If successful I can't see anything stopping expansion to the initial planned 9GW, other than capital funding.

There was an interesting City Journal article about fishermen getting in the mix that caught me by surprise in an interested party that never occurred to me before. City Journal has good historical background and context that they gather up on subjects too... "The mounting opposition to the development of offshore wind in Long Island’s waters is the latest example of the growing conflict between renewable-energy promoters and rural residents. Cuomo and climate-change activists love the idea of wind energy, but they’re not the ones having 500-, 600-, or even 700-foot-high wind turbines built in their neighborhoods or on top of their prime fishing spots. The backlash against Big Wind is evident in the numbers: since 2015, about 160 government entities, from Maine to California, have rejected or restricted wind projects. One recent example: on May 2, voters in three Michigan counties went to the polls to vote on wind-related ballot initiatives. Big Wind lost on every initiative." https://www.city-journal.org/html/bonackers-vs-big-wind-1533...

"'Not even Superman standing on Montauk Point could see these wind farms,' he said. Maybe not; and maybe wealthy beachfront homeowners won’t be able to see the proposed turbines, but lots of fishermen will. And that has them spoiling for a fight."

seriously? Why on earth does it matter if fishermen see wind farms? when did we invent the rule that all energy generation needs to be invisible?

I figured it was a simple matter of navigation and not crashing into these monstrous obstacles. I could even imagine it becoming a slalom sport of some kind if the danger was not too high risk. Something along those lines. Should be interesting to see the optimum grid layout for these things and how that scale of spacing compares relative to the average length of a fishing trawler.

The point is that they fear that fish will be scared away from the area by the presence of the turbines.

Is there any evidence to suggest that's the case though? A quick google suggests the opposite to be true. [1]

This reminds me of the middle-america folks who were claiming the wind turbines near their houses caused all kinds of disease, including somebody who claimed the wind turbines were causing people to contract aids. Not sure if it's just an unfounded fear of new things, or if it's a concerted effort by the fossil fuel lobby, but people really like to hate wind power.

[1] http://www.aqua.dtu.dk/english/News/2012/04/120410_Fish-thri...

If you're not keen on a big noisy ugly thing near your house, then the unspecified-risks-to-health card looks like handy one to play..

As I understand it, it's predominantly the noise that annoys people (At 110db up close, a turbine is equivalent to a propeller aircraft on taxi, and while most people hear the local town airport when the wind is in the right/wrong direction and/or there's a temperature inversion making the sound carry, those aircraft take off and are gone, while a turbine just keeps droning all day). ~60db has occasionally been measured near housing, and that's loud enough you'd have to raise your voice to talk -- not what people move to the countryside for, and as it's hard to get rid of a turbine after it's built they'll fight tooth and claw to stop it being built anywhere near them.

I think we're talking about offshore turbines. Who can hear 110 db from 30 km away? :)

The Navy could take a census of whale populations by having sonar operators listen for whale farts. Sound travels really far over water but even farther in water. The ocean is obviously a very noisy place but the long term environmental affects of what's essentially a white noise machine are yet to be known.

lol, that's quite the sampling technique. Whatever works right? Must be a pretty characteristic sound, but what a job right. "What do you do for work?" "I analyze waveforms for whale flatulence"

The one I was replying to was talking about objectors in the mid-west. Not much ocean in Iowa :)

> "My impression is that rich people who own land on the coast..."

Yep. An example:

http://www.cnn.com/2010/TECH/04/20/cape.cod.wind.farm/index....

Does anyone know what the status of using kite powered systems for off shore power generation is? I know makani has been working on that for over a decade now, it always seemed like a really promising approach to me but I haven't heard of any commercial applications of it. Here is a link to makani...

https://x.company/makani/about/

Kite power is one of my pet hopes. I keep hoping it will gain some significant traction. Looks like there may be a a test power installation going up in Scotland https://www.independent.co.uk/environment/kite-power-station...

What happens to these kite power stations when there's no wind to keep them flying?

The Makani ones that Google were funding are basically wing shaped drone planes on a tether, usually the rotors on the front of the wing turn in the wind to generate power but they use their rotors running backwards under power provided by the tether to land vertically back at the base when there's no wind.

When the jet stream dies we have bigger problems than a small drop in electrical production.

like what else?

>Lots of coastline is plenty windy. Why isn't there more offshore wind generation in USA like there is in other nations? My impression is that rich people who own land on the coast have no taste and think that offshore wind generation is an eyesore.

Offshore has promise but it's significantly higher in cost and there isn't a lot of long term data on how well they hold up yet.

> there isn't a lot of long term data on how well they hold up yet.

Whats your definition of long term? 26 years[1] is definitely getting there for me.

A part of the reason for that first farm being decomissioned is because new generation turbines are capable of generating more energy than the entire farm[2]. So maintenance costs per kWh are higher than the new gear.

[1] https://en.wikipedia.org/wiki/Vindeby_Offshore_Wind_Farm [2] http://www.4coffshore.com/windfarms/dong-to-dismantle-vindeb...

Some reasons:

- (lack of) political will

- abundance of cheap natural gas

- lack of US expertise (compared to Europe, where offshore wind has existed for decades)

- hurricanes

Now you are talking Florida home owners vs boat live-aboards.

I was shocked how windy Cleveland is. I'm told Chicago is more so. Windy city indeed. If its pratical to put wind farms in the North Sea off the coast of Scotland, I'm guessing using the Great Lakes would be too.

Yeah, that'll convince them to our side! Let's insult of their taste!

Never mind that taste is subjective, and you cannot deny that modern wind turbines don't exactly blend with the natural horizon, be it sky, mountain, or forest...

Well to be fair, skyscrapers don't blend with the horizon. Cell towers don't blend with the horizon. Cooling towers and smokestacks don't blend with the horizon.

The nice thing with coal and nuclear power is that rich people can push it's production to poorer areas and forget that there are major externalities to allow them to flip a light switch. Rejecting wind power because it [insert reason here] is just saying "make the poor people deal with it". It is quite literally one of the most selfish decisions anyone can make, to force the world to stay on coal power because wind turbines "don't blend with the horizon".

No. Don't make this a class warfare thing. The nice thing about nuclear/coal power plants is that you dont have to pepper the horizon with them. There is substantially less visual impact, and with nuclear, far less spatial footprint.

And plenty of people, rich and poor, oppose skyscraper construction because of view loss.

What is with this inane contemporary idea that we should not be able to use wealth to improve our quality of life? This is the ultimate form of empty virtue signaling. Why haven't you built a turbine on your property yet? I'd venture to guess that you're a well off developer, making you top 1% of the global population...

But it's ok, so long as you have your own 1% to sneer at, right? It's their fault that we dont have turbines!

Classism can be used for the same kind of scapegoating that racism and sexism are.

Because here's the argument: I need power. Right now I get that power from coal plants. That's bad, right? I think that's bad. Let's not do that. Oh, you mean to get wind power you need to put the windmill somewhere windy? But my house is windy! Nah, let's keep the coal, at least I can't see it from my house.

The inane contemporary argument is that you can use wealth to improve your quality of life. Like not burning coal to make electricity. Arguing that you'd rather stay on coal power than see a windmill isn't trying to improve your quality of life, it's actively destroying someone else's quality of life.

But the lungs of a poor person are worth less than the view of a rich person, so that's what happens. At least coal doesn't "pepper the landscape?" Jesus christ, man. No one is asking you to put a turbine in your backyard, you're just throwing a fit about the hypothetical potential to maybe possibly one day cast a glance at one, and rejecting the idea on that basis.

Did you know meat comes from dead animals too? Yeah, really pretty view from inside a bubble. Real nice horizon.

I am not arguing that we should stay on coal. I'm suggesting that you dont need to be an evil 1% banker to understand why both rich and poor people can be against windmills.

>No one is asking you to put a turbine in your backyard Sure, but it is going in someone's backyard, and it isn't as footprintless as people make it seem.

Poor and rich share the horizon alike; I would argue that you are the one in a bubble if it is so difficult for you to wrap your head around why people from all classes may not like wind power, especially when other options exist.I'll

>But the lungs of a poor person are worth less than the view of a rich person Why haven't you donated all of your income to starving children? Is your comfort worth so much more than theirs? Dont put words in my mouth.

You're refusing to analyse this from the perspective of cost/benefit. All I'm saying is that there is a non zero cost to choosing windmills over other alternatives, and it has nothing to do with classisim. There are documented complaints from farmers about noise and light problems from windmills.

Again, let me spell this out for you, I dont care if it is true or not, there are people who believe it, and it is subjective. Further, who are YOU to make the decision for the helpless poor that you guard over so arrogantly that a handful of cancer deaths in a region are worth a potential eyesore? You know that people still willingly smoke cigarettes, right? Are you smarter than those people? Are you prepared to look them in the face and say that YOU know better than they?

> The nice thing about nuclear/coal power plants is that you dont have to pepper the horizon with them.

Ahem,

https://www.google.com/search?q=open+pit+coal+mine&tbm=isch

The US is only 2000 miles wide so from the center that's just ~1000 miles which is fine even with normal power lines. You can do high voltage DC power transmission over 4 times that distance.

At non-negligible losses. (Expected about 10% for the whole system.) Not to mention maintenance of such long cable will be real hard, so redundancy is needed. (For comparison, check costs on much easier and cheaper transatlantic fibre cables.) And of course a facility placed further of the shore is harder to maintain as well.

10% is practically negligible when the power is coming from cheap wind power on the plains.

The 1200 mile Xiangjiaba–Shanghai HVDC line in China has transmission losses "well under 7%" [1]. This line was also completed almost three years ahead of schedule, which is an excellent contrast to Western nuclear plants that are being constructed in China. But then, nobody knows how to complete the AP1000 or EPR on time or on budget, as far as I can tell.

Lots of HVDC lines are going to be essential for cheap power in the US in the future, I just hope the political will materializes for that.

[1] http://3phasepower.blogspot.com/2010/08/xiangjiaba-shanghai-...

Edit: corrected the nuclear comparison.

> EPR on time or on budget

Sure, on one hand, this kind of project is likely to get into cost overruns. On the other hand, Areva looks like a fairly dysfunctional company following the tenure of Anne Lauvergeon, so it's not only a technical problem.

It's also the AP1000 from Westinghouse, not just Areva. There are definitely deep problems at the senior management level down to project management down to QA on welds with Westinghouse. I haven't followed Areva.

At least for the EPR they are building in Finland, AFAIU a lot of the delays and subsequent cost overruns have been due to stuff like poor welds or poorly done concrete that has to be redone. Really basic stuff that one would assume that a company that is building a nuclear power plant could handle, but, alas, apparently not. Of course, Areva is claiming that it's just the Finnish nuclear safety inspectors who are being overly nitpicky.

Yes, nuclear advocates in the US love to blame regulators and ignore the incompetency of their own industry too. There's a new report out today highlighting that at the South Carolina project that was just cancelled, there was an internal report highlighting lack of plans, unconstructable plans, low morale, and high turnover. And that the project was likely to fail. Three months after the report, an additional $800M was requested, and then 18 months later it was cancelled.

http://www.postandcourier.com/news/newly-released-report-hig...

Such behavior seems to be borderline criminal, particularly covering up the internal audit.

Yet this is par for the course on nuclear these days.

A lot of our problems are technically solvable with very near term technology. Yet we choose not to do it.

Not sure what you're getting at, apart from the loss the same disadvantages also apply if the cable is superconducting.

Even worse, maintenance and running costs of superconducting cables are likely much higher due to the cooling (high temperature superconductors are "high temperature" in comparison to other superconductors - there's still lots of cooling needed).

This is a problem that--well, I'm not going to say it's solved, but it's certainly addressed in an ongoing way. In the NE you have a lot of dinky little power plants burning coal and whatever else, but if you look at the NW there's huge hydroelectric. Hydro has to be located where it made sense to build dams; this hasn't always matched up with the needs of the grid. Long distance transmission is thus an ongoing reality. Power from Bonneville goes out to Montana today; it's not hard to imagine the reverse.

Just to add some data to this comment, WECC's "State of the Interconnection" (The line you're talking about is "Path 8"): https://www.wecc.biz/epubs/StateOfTheInterconnection/Pages/T...

Transmission is a solved problem, as far as regional power is concerned.

> "Not to mention maintenance of such long cable will be real hard"

Not really. You'd have to do periodic helicopter patrols of the lines themselves. There isn't really that much "maintenance" that occurs on the line, definitely on the xfmrs/rectifiers/inverters though, but that is normal for any transmission/substation owner.

Also, expected losses are ~5%

So you could lay a power cable across the Atlantic?

It might be physically viable, but I imagine that wouldn't be economically viable.

You responded to someone talking about laying a cable across land. So, no, they did not say that you could cheaply lay a cable across the Atlantic.

Of course, if we just wait long enough, the coasts will move inland, making then problem conveniently easier.

Yeah and after they build wind turbines inland and the coasts recede, the land owners will now start complaining that these now-offshore turbines are ruining their waterfront view of the sunken remains of Miami.

Not sure if it's relevant question here but here I go: I was driving from LA towards Joshua Tree National Park and I saw so many wind turbines which were not operating even though there was plenty of wind blowing and the adjacent wind turbines were running. Is there any reason they were not operating? Can't be maintenance problem as I saw so many not running.

I believe this is because wind turbines are brought online and taken offline according to demand. Nukes/gas stations can't have capacity adjusted very quickly, and take hours to get up to full production. Wind can be started/stopped quickly as demand rises and falls throughout the day

"Demand response may also be used to increase demand during periods of high supply and/or low demand. Some types of generating plant must be run at close to full capacity (such as nuclear), while other types may produce at negligible marginal cost (such as wind and solar)."[0]

[0] https://en.wikipedia.org/wiki/Demand_response

If the wind force is too much for the turbine/blades to handle I think that the blades are locked in place. Don't know if that's what you saw though.

If your base load (power that can't easily or efficiently be switched off; typically coal, nuclear and hydro) plus your renewable production exceed demand, then the best solution is normally to turn off some of the renewable.

It could be curtailment due to overcapacity or lack of transmission infrastructure to get the electricity to consumers [1]. I'm not quite sure why a more expensive source wouldn't be shut down instead, but maybe the unpredictability of wind power makes them the first to fall when demand is low?

1: https://www.greentechmedia.com/articles/read/why-arent-those...

The key thing is reliability and most Balancing Authorities will have procedures dictating which generation comes offline.

Perhaps turning off some turbines can provide a marginal increase in efficiency for the entire turbine farm?

It's cheap in the places that are windy. One big challenge (mentioned tangentially in the article) is in moving this cheap energy from the windy center of the continent to the populated coasts.

I wish this was higher priority, because the same X is already very cheap where it is Y is true of so many renewable sources like solar as well. And a wide power grid with long distance markets produces more consistent power since it averages different weather in different places and different power sources all together.

To make something that is cheap in X but not on Y cheap in both you must first overcome the entrenched special interests who make money from that thing being expensive in Y.

>To make something that is cheap in X but not on Y cheap in both you must first overcome the entrenched special interests who make money from that thing being expensive in Y.

Yes, it's a huge problem. States fight against buying cheaper power out of a state because they'd rather pay higher prices but keep the jobs and tax revenue in their own state. And on the other end, places that ended up with unusually cheap power (because the local market changes for example) sometimes oppose building out power lines that would enable the power to be sold nearby because it would end up increase local prices.

So many screwy incentives! Really need a power grid initiative.

>Yes, it's a huge problem. States fight against buying cheaper power out of a state because they'd rather pay higher prices but keep the jobs and tax revenue in their own state.

Every day I drive past a bridge being constructed. It's a bunch of 50-100ft steel arch sections that go between concrete islands in a shallow river. They would have been done last year if they had just ordered up a replacement and had it brought in on a barge then put it in place. Instead they'd rather spend the money on what's essentially a welfare/jobs program. I wish they'd at least acknowledge that angle rather than playing dumb and looking like they got ripped off.

cool ... superconducting ... yeah, har har, I get it.

Seriously though, is that really cost competitive compared with HVDC transmission which has losses of around 3%/1000 km?