Electricity Across Oceans: Is HVDC the Future? 

Hey, high voltage test systems engineer here. This is an awesome explanation video! I love the representation of HVDC you are doing here. Economic reasons and technological feasibility have a great balance here. You said the cables have a high capacitance due to their proximity to the ground or water. 4:10 While this is technically not wrong, the reason for the high capacitance is their outer, grounded sheath! These cables are under ridiculously extreme electrical stresses compared to open air transmission lines. Their insulation is quite high tech, but the sheath is a key feature. It homogenises the electric field inside the insulation, greatly reducing stress. Also, it keeps the electric field inside the cable, so the outside is (nearly) field-free. Very important as to not disrupt all kinds of stuff going on outside the cable.

It's so nice to have an Australian lady to teach us about AC and DC.

Where I live (Manitoba, Canada) we have three HVDC transmission lines in operation. Most of our power is from hydro and the vast majority of it is produced in the northern part of our province on the Nelson River. Most of that power gets consumed in the southern part of the province and back in the early 1970's two HVDC lines were run north/south. These were known as Bipole 1 and Bipole 2. These two line were run side by side in the same right of way and in the 1990's a tornado knocked both of them down. In the early 2000's it became necessary to run a third line and for security reasons (both weather and terrorist) it was decided this third line should be run down a different route. This is were the story veers from engineering to politics. The best technical route (i.e. shortest) was down the east side of the province. However, the government of the day decreed that it would run down the west side of the province. No amount of reason would sway them and the engineers in the project remained quiet for fear of losing their jobs. The retired engineers from the original Bipole projects had nothing to worry about and there was a constant barrage of reason and logic aimed at the government in the opinion section of the newspapers of the day. They christened it the "Western Manitoba Heater" and pointed out that the extra 200 MW of line losses over the east side route would consume all of the power of the most recently completed dam. None of it worked and Bipole 3 was built on the west side for considerably more money than the east side route and will now lose an extra 200 MW in perpetuity. It's no wonder you see so few engineers in politics.

We also have an HVDC across the ditch in NZ connecting hydro in the South Island to the population centres in the North Island.

The map showing your Trans Atlantic 'sub sea' cable route, omits the Republic of Ireland, through which your cable must go, if it doesn't take a huge detour.

Wouldn't it make more sense to connect the UK to Faroe, Faroe to Iceland, Iceland to Greenland, and Greenland to Canada? That avoids many of the problems associated with super long cables, as well as avoiding some of the deeper seas. For example, From St. Ives in the UK to St. Johns in Canada (the shortest possible stretch), the cable would be over 3,000km long and have to be over 4.7km deep in some areas - most of it 3km or more. By comparison, from Thurso in Scotland to Kirkjubomururin in Faroe (415km, depths mostly in low 100s, with the middle dropping to 1km), Eioi in Faroe to Faskruosfrorour in Iceland (450km, depths mostly below 500m), Isafjorour in Iceland to Kulusuk in Greenland (640km, depths mostly below 600m), and Narasarmijit in Greenland to West Bay in Canada (1000km, of which around 800km drops to 3.5km but avoids the mountain range down the middle of the Atlantic. Add around another 800km between Kulusuk and Narasarmijit around the coast because it doesn't look like Greenland have an electricity grid, and I don't foresee anyone building HVDC across the landmass. This seems a lot more achievable, not to mention cheaper, than trying to lay a cable straight from the UK to Canada, and adds the benefit of Faroe's hydro and Iceland's geothermal along the way. Both, as well as Greenland, could probably turn themselves in to major energy players, with landscapes highly suited for hydro and pumped hydro. Well, in the summer, at least!

Electrical engineer here: Only benefit of AC is cheap and efficient change of voltage inside transformer. Now, with modern DC-DC converters, they are almost as efficient. Benefits are: Grid does not have to be in synch any more, as all is DC, so whole world can be connected. Power routing is easy, as you need to have a little adjustment to direct flow of power, by boosting voltage a little on power line. Efficient home solar instalation, as you would not need to convert it from DC to AC for appliance use and just use 240V solar battery (or central tap 120-0-120 in split phase system). Most device in home can run on DC power supplies: Any swtich mode power supply (chargers, PC power supplies) Stoves and other resistive heaters (like boilers) Most LED and all incadesent lights Devices that can be adapted: Any device with universal motor (vacuum cleaner, blender), but you would need to give up speed control or change the circuit Inverter air conditioners and fridged Devices that would not work on DC and need am inverter to work: Anything with old iron core transformer Anything with an induction motor (fans, pumps) Anything with a dimmer circuit (ligjts, vacuum cleaners) Clocks dependent on grid frequency

Always wondered why DC was being used for these long links while most long distant lines are AC. Thanks for the explanation!❤😊

600 million for eleclink? That’s how much the feasibility study would cost in Australia

Sadly I have but one thumbs-up to give your excellent video

I had not realised my physics was so rusty, thanks for the refresh 😃

Since 1992, Hydro-Quebec already operate a 1500 km of DC line. They are looking to get many more of them online soon. The current line is transiting about $1M in electricity, every day. Regarding politic, it already a problem for Hydro-Quebec (Canada). The state of Vermont (USA) is dependent on HQ. Furthermore, The state of Massachusetts (USA) often consider that it will be imprudent to get more electricity from Quebec. New-York city is also VERY Reliant on HQ. HQ already supply some electricity to Ontario (Canada). All in all, if HQ were to shut down the delivery of electricity to New England, the NERC NPCC regions will likely crash. That the reason HQ looks at Europe. HQ is 94% Hydro. It does want to develop the WIND resource too. So, with Europe, what HQ will like to do is become the"BATTERY" where it does purchase electricity cheaply on the European market... and resell some when the sun is not shining or the wind not winding enough. HQ has an impressive amount of dispatchable electricity with Hydro.

For years now, Norway and The Netherlands are connected as well ... North Sea. The Dutch also have an energy platform island in the North Sea, this allows connections with sea based wind farms (windmills connect to the platform, operational already!). The platform provides an opportunity to connect with the UK grid. Another Danish - Dutch platform will be built for more Dutch and Danish wind farms and to connect Danish and Dutch grids. Sea based connection platforms can be the interconnection nodes in cross sea networks.

Fantastic video, plenty of information which is easy to understand and no in video ads. I'm going to show my daughter your videos as she's in high school right now and i've shown her engineering videos for a few years now and she's quite keen on becoming one and I think you'll be a real positive influence on her :)

Excellent video with a good explanation of DC vs AC line transmission for this non-engineer- thanks!

Very nice summary Rosie. In my view, you've got the level of detail exactly right.

Love the new production setup. I hope this upgrade doesn't cost a fortune, sure seems professional and very enjoyable to watch!

This was an awesome video! I remember my Power Engineering professor talking about this stuff a year ago. It seemed like such a cool idea, but I never even thought of its potential to unlock renewable energy. So cool that this is happening!

Yes, geopolitical insecurities are likely to become more and more important issues to factor into undersea HVDC. While battery storage (from pumped hydro to various cell chemistries) is seemingly more expensive, I believe the cost/kWHr storage will abruptly fall year by year in the next half decade as newer and more cost-effective stationary storage plants come on line around the globe. Furthermore, it is MUCH easier to use such storage to smooth peak-demand on grids locally. And last but not least, the massive and enthusiastic trend for home owners to go solar and also contribute to virtual power plants has been proven in the UK to remove massive stresses from ageing and (currently - no pun intended) inadequate electrical grid structures. B.T.W. Seriously clear explanations in this one Rosie. Thank you.

Fascinating insight into the financials behind HDVC - thank you. 🙏

In the winter you can get a few extra hours of solar power in your system going north to south. It's always a 12-hour day at the equator. If you're lucky enough to get some place on the other side of the equator you can get Summer sunlight all year round

Great video! You mentioned connecting Montreal to Liverpool. That means connecting to Hydro-Quebec, a vast and not fully utilized resource. It generated about 225 TWh in 2022, an average of 25 GW. Quebec itself uses about 80% of that. HQ has been trying for decades to get links down into the US Northeast, but they get blocked by local opposition. E.g. there was to be a line across Maine down into Massachusetts that was strongly supported by the state of Maine, but delayed by a referendum paid for by a Florida natural gas company. It's not quite dead, but in a coma. The nominal reason was the effect of the power line right-of-way on Maine's forests. Running an undersea cable down to Boston and New York might actually be easier! I also keep hearing about HVDC from Iceland to Europe to distribute geothermal power, but so far it seems more economic to use the power to make aluminum. HQ does that too.

Thank you Rosie. My first reaction to the notion is for us to do everything we can, genuinely green can, before we embark on the massive deployment of resources to yet another piece of infrastructure. If we can get by without it, we must. If we cannot get by without it, we must do it. I cheering for the side that says we get by without it.

Hello! High voltage cable engineer here, you are awesome! What a fantastic short video summarising what is happening in the world of HVDC cables!

Hi Rosie, great video! Interconnectors are incredible and we need more videos like this one to help inspire future engineers! Just as a small FYI though, ElecLink does not make it's money from buying power in one country and selling it into another. The revenue is generated on a capacity auctioning platform called the Joint Allocation Platform (JAO). Basically energy companies can auction for the rights to transfer power a cross the cable and ElecLink recieves the money from each auction. The only time ElecLink would ever buy power from one country and sell into another would be during the commissioning phase of the project.

I think it would be more profitable to link Scotland to Faroe, then on to Iceland, Iceland to Greenland, then finally down to Canada. Total route 4,400km but in ~1000km spans makes it easier to swallow. Iceland being connected to Europe and North America would be amazing given Iceland's renewable energy supply capabilities. The hydroelectric potential of Canada then being linked in makes it very special.

This is the best summary so far

10:45 You mention Montreal. I think that I need to correct one very important detail about Québec. We have very little solar power. Almost all of our power needs are provided for by giant dams located a thousand kilometers north of the population centers. There's also a number of wind farms. In eastern Canada, the potential for wind energy is greeter than solar. It probably would be the right place to connect an undersea cable given that the power grid is rather well developed in Québec. Eastern Canada has gotten a few upgrades with the lower Churchill project, and there is room for another dam to expand capacity.

Excellent video! Very informative as always! 👍

BTW, when we talking so much about connecting countries and even continents in one grid, why is some countries (like US or Australia) actually have several NOT connected grids one close to another? Like US have so much timezones, that sunshine in a one cost will provide power for the twilights time in another. But somehow in US they still have 3 separate grids. Why? Same question about Australia

I never thought about the capacitive losses of ac cables in land or water. good video.

Wow this is fantastic. Thanks for the video!

13:20 love it. Dunkelflaute!! I did not know this german word got integrated into english language.

Really pleased to see the use of non pumped hydro as a battery for wind and solar. I was very surprised when commentators assured me that only pumped hydro could be used as such for reasons that were far from clear. If only the electricity market in NZ was somewhat sane, we should be doing a lot if this here. Savecthe hydro for when the wind isn't blowing.

This is so cool. A quick note for 5:55, that €420m is income (revenue), not *net* income (profit). And the profit is what makes the system "pay for itself", not the revenue. If ASDA makes £1B in revenue, but it cost them £1.2B to make those sales (from the cost of buying the products, paying the employees, renting the buildings, etc.), then they've lost money, even though revenue is high. In the Getlink case, it still looks like their net income (profit) is very high, so the effect on investors in the industry is likely exactly as you say. But it would still take 3-4 years to pay for itself, even though that's a really quick turnaround relative to other industries. Cheers!

Excelente explicación sobre HVDC, greetings from 🇪🇨!!!

Very interesting. Very long cables in the order of 1 km will also radiate energy (think very low frequency radio). I really enjoy your rational, well-thought out videos, with no hype, you are one of a kind on RU-vid, actual expertise with no axes to grind!

The graphic at 1:00 appears to show a connection between the Isle of Man and Marystown, Newfoundland, not between Liverpool and Montreal. And most of Ireland is missing.

Your videos are fantastic and unmatched. You have been a great resource throughout my studies. Thank you for making these great resources.

This excellent video prompted me to read the Wikipedia article on the NZ "HVDC Inter-island" link connecting hydro in the South Ssland up to the North Island which has an interesting history of upgrades since it was built in the early '60s.

How about HVDC across Australia and hook WA into the National grid?

thx. for the informational video. You said the DC power losses over long distance is ~3%/ 1000 km, what is the comparative loses to AC power for the same distance?

Very well done. Thank you for explaining all of this.

Thank you for sharing.

There is a problem for long-distance cables… A transAtlantic cable must cross the mid-Atlantic ridge, which is where the two tectonic plates are moving apart (a few centimetres a year, I think). But I trust the engineers know this and plan for it. Although, 19th century engineers did not know about it, but the telephone cables were just fine

Very interesting, as always!

Really good❤ presentation of energy transfer. I remember college days many moons ago. 🙂 if only we had a lecture like that the math would have been far easier. Understanding the problems and fundamentals is really important not just studying for the exam.

High temp superconductors would be icing on the cake .

Can you talk about the energy losses at the AC->HVDC and HVDC->AC conversion stages compared to the high voltage AC step up and step down transformers?

There are two more uk projects in the works too. One to connect to Germany, and another to connect to the Orkney islands (off north Scotland) to tap into the wind and tidal potential. Great videos Rosie, thanks.

Very practical with engineering problems to solve and current costs. Thanks.

Well done this was my first video I've enjoyed of yours. I look forward to many more. xx

What is the voltage limit for HVDC? 1 million Volts like in China? Or it could be made to higher voltage like 10 mil or maybe 100 mil to make intercontinental power link much more viable and accelerate the transition?

Amazing new set! Any plans on adding more props and some dampening for the echo? It would definitely improve the already astonishing quality!

Hi Rosie that is a bloody awesome summary of the matter, putting it in the Australian vernacular.

With how incredibly intertwined the Canadian and American energy grids are (not including Texas, friggin' Texas lol), developing HVDC connections from likely Newfoundland to Ireland or the United Kingdom, and then making sure its connected accordingly to the European Union, we can greatly tackle major energy concerns. This would only further act to intertwine NATO nations, which would honestly be a really good thing.

Thanks for the vid! In looking up undersea cable laying, I found out about floating solar farms - curious to know your thoughts!

Great video. Can you please consider covering Japan's odd 50/60hz HVDC interconnects in another video? Benefits or challenges would be super interesting to hear.

Absolutely brilliant video!!!

This is a revolutionary idea. However appropriate technical, financial and geo political challenges needs to be overcome and same will and appropriate partnerships and interest needs to be appropriated to bring such mega projects of GW's distribution across Continents, into fruition. 🎉

Thanks for explaining HVDC in lay persons terms. For many years I was told only the only way to transmit power over vast distances was by high voltage AC. HVDC makes so much sense over long distances for all the reasons you have highlighted. I wonder if a country like Canada that has a small wide spread poulation can benefit from replacing overland HVAC lines with HVDC transmission lines?

Fantastic breakdown. I've been surprised how few people even know HVDC exists!

Wow, excellent explanation! Brilliant. Thank you.

An excellent video. Thank you.

Thank you for another well-explained evaluation Rosie. You mentioned the move from Cu to Al due to weight concerns. I keep hearing from a friend that "the world is running out of Copper!!!" as a reason for not moving to anything like 100% renewable power. I have not seen any reliable data put forward in the "debate", so I gather this is more of a reactionary trope than a real shortage. Do you know what the basis of this claim is? Is it a valid concern?

It's not just politics - these connectors offer a wonderful target for an enemy. I think they are still far to attractive to give up on.

My guess is Canada and the UK get along well enough that they would be all right sharing power lines.

Thanks for the explanation, as a civil engineer my knowledge of electrical things is very limited. As a Canadian, I’d like to point out that Montreal is no where near where you labeled it! It would be better to end that transmission line in Labrador as that is where the bulk of the hydro generation is. There is currently a proposed transmission line from Eastern Quebec to NE US that is being block for running through wilderness areas. I wonder if an undersea from Labrador to Massachusetts would be feasible 🤷‍♂️ Thanks again

I'd love to know more about the inverters that handle the super high voltage DC. Do they use conventional semiconductors in parallel, or are they large single unit devices that don't use silicon in the same vane as the old mercury rectifiers?

As a German, I was surprised to learn that the word "Dunkelflaute" has made it into the English language 😅

A superb video, thanks for all of the info!

I like to learn more from you all. Thank you for sharing.

As always, a great video and an excellent explanation on the causes of loss on AC lines. When I read about the UK to Morocco HVDC project, I wondered why would they do that. It doesn't seem to me to make sense to have a direct line to a single source of power which, BTW, doesn't get any sun when you are both at night, when you could make shorter parallel connections to continental Europe and get into a big grid that spans multiple time zones and expand the connections from there to Morocco. You need far less resources (cable, ships), transmission losses and exposure to harm with multiple connections both by land and the sea than a single set of cables. Plus, you have the advantage of making money by sending power both ways. Am I missing something in the technical side? My first reaction was that there are some clever guys selling the project to a brexiteer government willing to waste money on anything as long as it bypasses the EU. Thanks.

I think that the future belongs to decentralized systems. Each household, each settlement, each section of highways can have its own sources of renewable energy and its own energy storages connected with neighboring ones. And large power plants will be needed only for large factories.

Best description of skin effect I've heard! I loved the video!

Brilliant! Thank you.

Rosie this is amazing! I've been preaching this EXACT thing for a decade! But it should be broken up into segments. I've been talking about a Canada -> Greenland -> Iceland -> Faroe Islands -> Scotland/Norway HVDC link so much that my engineering friends just roll their eyes when I bring it up. It just makes so much sense. Each link in that chain has huge value and can stand on its own right, but together it makes renewables make sense WITHOUT the huge reliance on storage. Canada has been desperate to electrify Northern native communities for ages and will fork over boatloads of money for anyone willing to do it. Greenland needs cheap power. Iceland is begging for some way to export their surplus of energy. Faroe Islands uses expensive dirty old fuel oil for electricity and this would be a boon for them. And the math works out with current technology. You don't need any crazy year 3000 science fiction superconductors; it can be done with existing cables. And Siemens, GE, Hitachi and (I think?) ABB and Panasonic are already manufacturing the inverters. It just makes too much sense.

Interesting video, thanks! Do you also know about Ultra-high-voltage DC or UHVDC? I have been reading that there are several in production already, especially for long distance (thousends of kilometers) . They work with voltages up to 1,100 kV and are supposed to minimizing transmission losses. Notable examples include the Three Gorges-Gezhouba-UHV DC transmission line in China, the Rio Madeira HVDC link in Brazil, and the North Sea Link connecting the power grids of Norway and the United Kingdom.

This is an excellent video, I plan on showing to my non-engineer colleagues when they ask about HVAC and HVDC. We build offshore wind with both types of transmission systems but people who are not power system engineers struggle to understand the differences.

Very informative and well presented. Love the new studio setup with different camera angles. The visuals were outstanding and well integrated into the presentation. Thanks for doing this.

I like how the map just deleted Ireland and pretended there was nothing West of the UK all the way to the US. Sounds like the dream of many UK governments

Seems like a lot of work to just avoid building more nuclear power plants and more hydroelectric dams.

It's a funny situation in the UK regarding engineering infrastructure across beautiful natural scenes. The Romans started it with their viaducts and then in Victorian times the great Brunel built these vast structures for railways and suchlike spanning valleys. You never guess what though. In our tourist brochures they are photographed and displayed as tourist attractions. Meanwhile 21st century engineering projects are violently opposed on the grounds of environmental damage. It seems they need to age a hundred years or so to gain poplar approval!

Just came across your channel and instantly subscribed 🎉🎉 , btw i was doing research on different methods of energy export , and came across the idea of flow batteries. Do you think these types of batteries would be a good candidate for energy export ? Since the power and energy a separate and we could export the anolyte and catholyte (in theory ) Would love to hear your thoughts on this 😊

I would love to know how the inverters on either end (AC to DC... DC to AC) are done. Is it possible to do solid state at these voltages, or is it 'tubes'? What is maintenance like? What are the failure rates? Is there automatic switchover to a backup, etc. Thanks!

Subscribed. Great quality video. Thank you.

Very good video, many thanks, Rosie.

Perhaps we should have engineers solve more of our political problems. Vote 1 Engineer Rosie for benevolent dictator.

So, the main barriers are capitalists and politicians, eh? 🤔

Wow, it's so cool that those first two links paid for themselves so quickly!

The Basslink cable slashed the communications cost to the island - as it contained 24 cores of fresh SMOF. It broke Telscum's monopoly on the route - and added 100's of GB to the island.

As we have seen with gas lines, there is also sabotage.

Or ... hear me out ... just build out nuclear power 🤷‍♂

This is not only a good idea economically, but also politically for the western blocks.

Montreal is a very appropriate choice as the western end of your proposed trans Atlantic cable as it is probably the largest city in the world that achieves 100 percent renewable electricity and does so for a far lower price per kw/h than anyplace depending on wind or solar. Unfortunately many people who want to see renewables replace fossil fuels seem to be completely opposed to what is the most viable. It would not be solar energy from an area that sees sun twenty hours a day that would keep the power on, it would be the massive hydropower dams north of Montreal

What a great explanation with the animation.

Wow, lots of great info about HVDC. The 3 sources of losses and the details about the cable were especially interesting. Just a small nit. At 10:33 your HDVC cable is going to the province of Newfoundland in Canada. The city of Montreal is in the province of Quebec, about another 800km west. Love your videos.

So interesting! Thanks a lot. This is my favourite RU-vid channel ❤

It's a shame that people talk either engineering or politics but never integrated. A collaboration would be so sweet.

Really excellent video