Announcement of a wiki for serious discussion of the future DC grid

Clay Taylor, who works with me, suggested we create a wordpress wiki that discusses the future grid. We think it is unavoidable that the future grid will be all DC; I think many of you will agree that in 100 years, the grid will be DC. That implies a transition; few would predict that the transition to DC would occur within 20 years (I think that 30 years is possible). It seems to me that most tech-savvy observers would agree that a transition to a fully DC grid will occur between 20-100 years from now, So lets discuss this! Some of my past posts, especially my discussions of ground return currents, would logically fit into this new website, which will be DCgrid.network. As of today, that url just forewords to this blog post.

I'd like to hear from you if you are willing & interested to participate. Clay Taylor will be webmaster, and both he and I will be regular contributors. In various posts on this site, I have included snippets that originated from various luminaries in the development of DC technology, starting with Bill Long at UW-Madison, who was my expert witness in the 1991 Wisconsin Public Service Commission Advance Plan 6 hearings, but also including Gunnar Asplund (formerly in charge of HVDC development at ABB), Stig Nilsson (currently a VP at Exponent), and others.

This wiki will be gently moderated, but I'm not looking to exclude folks who disagree with me. I hope to create a lively conversation, based in science and technology, but also willing to look at things like cost of right-of-way (ROW) and cost of legal fights around obtaining ROW (this is relevant because it is easier to put DC power underground for great distances than AC). Also discussion of other environmental and health effects of DC versus AC power might be nucleated there if an appropriate expert comes forward to focalize that.


Mesogrids as Stepping Stones to a Supergrid

Sometimes creation of a new term has a way of crystallizing a new concept. I hope that "mesogrid" will work that way. I envision mesogrids as evolutionary steps towards a supergrid. I give Steve Eckroad credit for the mesogrid concept, though it was my idea to introduce the term. This figure from Steve's US Patent 7,518,266 (assigned to EPRI) illustrates the concept:
Essentially, a mesogrid is a DC grid that connects into an AC grid at several AC nodes (major transformer yards in the above sketch) and so has both transmission and distribution functions. Steve envisioned an HVDC loop around a city as a way to improve reliability and resilience against rolling blackouts. Mesogrids are differentiated from microgrids because of connecting to the AC grid at several points, and are smaller and lower in operating voltage compared to future supergrids. This makes them very well suited as intermediate steps towards supergrids. Below is an abstract for a paper I plan to present at Distributech 2016:

(Update September 22, 2015: the paper was rejected. I still plan to pursue this idea, possibly with different co-authors.)

Mesogrids for Flexible Energy Distribution
Roger Faulkner and Clay Taylor (Alevo R&D); Randell Johnson (Alevo Analytics); and Steve Eckroad (EPRI): DistribuTech 2016 abstract 

Mesogrids are proposed DC grids positioned between large long distance transmission lines or central generators and smaller distribution substations, up to the scale of backing up a city power supply. The concept was introduced by Steve Eckroad of EPRI in a patent[i], mainly directed at protecting an urban area from a rolling blackout, but the same basic design also facilitates two-way energy flow due to distributed generation, and increased use of shared, non-local energy storage. This patent describes a mesogrid sized for an urban area, taking the form of an HVDC loop around a city, connecting all the major transmission substations around the city by DC. Eckroad envisioned high temperature superconducting (HTS) lines to accomplish the DC connection, while we envision conventional conductor-based HVDC mesogrids based on elpipes[ii], overhead lines, and cables. Elpipes are polymer-insulated metallic extrusions, linked through flexible couplings, which run on wheels within a pipe, which are being developed by Alevo. Current for an elpipe can be much higher than a cable, simply because more aluminum/meter can be used economically with the elpipe design. Elpipes make it feasible to transmit more than 6kA, allowing GW-level transmission at 80kV. If elpipes form the backbone of a mesogrid, resistive loss through the mesogrid conductors can be kept below one percent.
Mesogrids are between current AC grids and typical microgrids in size and voltage. As with DC microgrids, mesogrids facilitate two-way energy flows in a system containing a lot of distributed generation. Mesogrids are distinct from DC microgrids both by moving more power and because they may link into the AC grid at multiple different substations. Like the future supergrid, mesogrids are envisioned as DC grids that parallel and reinforce the AC grid. Mesogrid voltage will typically be around 80 kV, and represent an evolutionary step towards a future supergrid, at voltage levels which are safe and compact, yet realistic for GW-scale transmission.
Systems that could be powered by mesogrids range from a large industrial or data center complex, to a city, or a region with numerous energy farms and energy storage sites. Optimum voltage for mesogrids is well below typical HVDC transmission voltage (300-800kV). Like the future supergrid, mesogrids are envisioned as strictly DC grids; voltage will be most economical for the envisioned applications around ±(30-180) kV, which places them in the voltage range bridging between MVDC and HVDC. Power levels at ±40kV can conveniently be 2 GW (6250 amps) if the connections are based on elpipes (lower power mesogrids could be based on cables). This work demonstrates the utility of mesogrids at several power levels, including urban area power reliability enhancement as originally proposed by Steve Eckroad.

Mesogrids also make sense as “collector buses” serving several renewable energy farms and energy storage facilities (such as batteries, dispatchable hydro, and pumped storage) as well. By aggregating distant energy farms with several different time-scale storage devices, mesogrids can deliver firm renewable energy at lower aggregate cost than if each energy farm had to firm its own power. In rural areas, segments of a mesogrid loop to serve remote energy farms and storage sites might be overhead lines, though at 6kA as would be required for a 2-4 GW mesogrid loop, multiple parallel overhead lines would be required if part of such a loop is implemented via overhead lines. Because of their high ampacity, elpipe loops are particularly good candidates for initial application of mesogrid technology.

Elpipes are high capacity segmented DC conductors that are based on polymer-insulated pipe-shaped conductors (think bus pipes) rather than wires; the segmented nature of elpipes allows far more conductor per meter of line to be used than is possible for cables, which must be able to wrap on a reel. Elpipes are capable to carry much higher current than cables or overhead lines. By moving high capacity DC transmission underground, elpipes make installation of a mesogrid linking substations in an urban area more politically feasible. Unlike cables, elpipes will be readily repairable, as they sit on wheeled carriages inside underground pipes. Elpipe repairs can be made rapidly by swapping out faulted segments, and the elpipe will not have to be dug up for most repairs.

At a smaller scale, mesogrids are an ideal way to distribute power in a DC power environment. The main high-current connections of a mesogrid could be overhead DC lines, elpipes, gas insulated lines (GIL), or HTS lines. If maximum current is 2kA or less, mesogrids based on HVDC cable are also feasible. We present as an example of such a small mesogrid, a datacenter.
HVDC mesogrids make sense for underground energy exchange over a region with many terminals. We present for consideration three particular examples of power systems linked by mesogrids:

  1. 100 MW datacenter complex, where the advantage comes from sharing backup capacity, and from very low transients on the DC datacenter buses (per our definition of a mesogrid, this needs to tie into at least two different AC substations, otherwise it is a large DC microgrid);
  2. a small city, where the DC interconnection of substations facilitates two-way power flows in areas with lots of distributed generation;
  3. a region with numerous energy farms and energy storage facilities, where the DC grid enables firming of power from several energy farms and energy storage facilities, where the primary advantage is due to being able to firm power with less total energy storage online.
These three cases represent realistic size scales as particular examples of mesogrids. The smallest mesogrid, Example 1 corresponds to a demonstration project at Alevo's 2000-acre North Carolina factory campus that would be capable to provide fully backed-up, high quality (low voltage fluctuation & low transients) DC power to 100 GW of new advanced industrial and datacenter loads, with high reliability and power quality guaranteed by on site back-up resources.  Example 2 extends the mesogrid to the region around our factory (the town of Concord, NC or the city of Charlotte; not yet decided), via elpipe links and VSC AC/DC converters at numerous substations in the town of Concord, NC. Finally, Example 3 considers a mesogrid extending around a city with high solar penetration and nearby wind farms (site not picked). These cases are not modelled in full detail, but thoroughly enough to visualize the cost/benefits at each scale.
Any DC grid with power levels over a megawatt has a significant problem with circuit protection, and circuit protection generally costs much more than for an AC grid at the same power. In order to simplify modeling, all mesogrid cases analyzed use a single DC loop (MVDC or HVDC), as shown in the cited EPRI patent; there are both main loop circuit breakers (rated for maximum power of the entire loop), and fast disconnect switches on the main loop between every pair of power taps. One can obtain the n-1 redundancy level for every tap on such a loop, by placing a circuit breaker between every next neighbor set of power taps on the mesogrid. Such fast isolation is very expensive if the main loop circuit breakers are based on power electronic hybrid breakers capable of operating within a few milliseconds; for full redundancy one would require as many full-load circuit breakers as there are power taps. We consider an economically optimized solution for each power level, in which there are only a few full-load circuit breakers on the main loop, supplemented by fast main loop disconnect switches between each next-neighbor pair of power taps (AC/DC converters). In addition, each AC/DC converter is protected by relatively small circuit breakers.

[i] Steve Eckroad, US patent 7,518,266
[ii] Roger Faulkner & Ron Todd, US patent 8,796,552


HVDC Grid Requires Much More Economical Circuit Breakers

I think the crux issue holding up HVDC penetration right now is that so far, all HVDC projects rely on the AC grid for redundancy. That means that the maximum size of any HVDC project is artificially constrained by the local AC grid, and in effect guarantees that HVDC projects cannot carry more power than the biggest AC lines in the area. I wrote about that in several places, but this specific post gets at it directly:

Some day, we'll have a meshed grid, but right now the next logical step is to a multi-terminal HVDC loop, with circuit breakers between each next-neighbor set of power taps. Such a setup is self-redundant. The circuit breakers are the problem. In spite of ABB's claim to have solved this problem:

their solution is too expensive to work economically; I estimate their hybrid breaker will cost about one fourth as much per kW as a VSC-based AC/DC converter, about $35/kW (200 times as much as a comparable HVAC breaker). That is a big problem, and is one I'm working to solve with my Ballistic Breaker:

It is not enough to just have HVDC circuit breakers at each power converter, to isolate it from the loop; for full protection and self-redundancy, one needs main loop circuit breakers and those must have higher capacity. Take as an example a 10 GW loop with ten power taps, each with capacity from -2 GW to +2 GW. Ten 2 GW breakers will not be adequate for self-redundancy; one needs main loop breakers rated at 10 GW BETWEEN the power taps, which increases the cost by a factor of 5 (approximately). Thus, a lower cost HVDC circuit breaker is crucial. 

This post describes how an HVDC loop can answer Germany's need to move offshore power to Southern Germany:

Any circuit breaker for this application (HVDC supergrid) has a severe problem with current inrush in a fault. ABB in their hybrid breaker design has used a large inductor to delay the current inrush long enough to open the fast mechanical switch far enough to prevent re-striking. Unfortunately, an inductor stores energy as it slows the current inrush, and all this stored energy must be dissipated to open the circuit. A second way to slow the current inrush in a short circuit condition is via a superconducting fault current limiter (SCFCL). There are numerous patents in this area, and several known approaches to trigger the quantum mechanical transition of a superconductor to a conventional conductor or semiconductor. I believe the efforts of Paul Brown of Varian Semiconductor (now part of Applied Materials) are particularly promising, as Applied Materials is a new participant in this market, with no vested interest in the status quo, Here is Varian's recent patent. The use of SCFCLs as part of HVDC circuit breakers of other designs will reduce the cost of the main breakers by decreasing the maximum current that can develop before the circuit breaker completes its action (and therefore reducing the maximum rated current and voltage of the primary breaker).

Part of what is needed is to be able to carry a lot of power (10+ GW per line) in an underground transmission line; my solution for that is the elpipe, a sort of mashup of a powerline, a pipeline, and a train. I am now engaged in making elpipes (for underground HVDC transmission) and Ballistic Breakers (lower cost HVDC circuit breakers) work to make this vision possible. I have the support of a visionary investor (Jostein Eikeland) and his amazing startup company (Alevo) behind me. It will not be easy, but it looks feasible to me, from the inside. 


Too Bad Nuclear Energy has been so Mis-Handled

I posted this on the Claverton web site today

Too bad nuclear has been screwed up so badly. To me, it seems obvious that nuclear reactors should: 
  • be strictly sited in ships or preferably submarines. The entire plant, or at least the reactor should be movable. This would greatly facilitate decommissioning, and siting well away from cities. One could also move the reactor around where it is needed.
  • Move the cooling of nuclear power plants away from evaporative cooling and towards direct cooling with deep ocean water in such a way as to cause upwelling of nutrient rich water, increased precipitation in targeted areas (to increase available runoff or winter snow), and to increase thermodynamic efficiency of the power cycle.
  • We should have pursued the thorium 232 to uranium 233 break even breeder cycle. This obviates the need for enrichment plants to produce fuel. The total number of loose neutrons produced in U-233 fission is reduced compared to U-235 or Pu-239, meaning less total radioactivity.
  • The US Navy has a great safety record, and possesses great designs for modular nuclear reactors. Why does the whole debate on "modular nuclear reactors" ignore that? How is the idea novel? Why not use what we've got? 
  • I have not even seen a peep about what I consider the best option: building complete power reactors in submarine hulls that rest on the ocean floor in water just deep enough to be immune to surface storms. I'm pretty sure that the resultant upwelling can be managed so as to produce pockets of ocean fertility.
  • When I learned about LENR reactions of H + Ni I was struck by the fact that no thermodynamic laws were breached, so I think this may be real. That would certainly be a game changer...but if true, we would soon be confronting thermal pollution on a grand scale. We would still need a supergrid in that scenario, but for a different reason (to put the waste heat where it belongs).
Too bad the whole nuclear debate is so stale. Some new ideas could possibly break through the impasse.


ABB progress on HVDC cables

I have linked HERE to an ABB presentation on their new 525kV polymer-insulated cables. Great work!

This article from the Charlotte Business Journal says that ABB's Hunterville, NC plant will be making this cable, which surprised me a little. I would have thought this would be applied first to subsea cable, which can have thicker insulation due to its large-diameter reels.


Second Elpipe Patent Application Covers Wheeled Cables in Conduit

My first patent application on elpipes as originally filed had 73 drawings and 84 claims, and was filed as a PCT application. When this was finally granted and then published, on August 5, 2014, US Patent 8,796,552 is 69 pages, and 20 claims. I also filed a continuation patent in the US, which was published on July 24 (2014/0202765). The continuation must rely on my original specification, which was very detailed. I added claims on these concepts:

  • The continuation generalizes the concept of elpipes to also encompass cables on wheeled conveyance inside a pipe, and

  • cryostat containing superconducting line inside on wheeled conveyance inside a pipe

 From a practical point of view, this extends the range of elpipes to also include very thick cables (similar in diameter to subsea cables, but potentially much less expensive because of lacking armoring and tow-strength layers). The recently announced breakthrough by ABB on 525kV undersea cable makes this all the more important. I blogged about the "wheeled cable concept" previously. This method could also be used to string a spliceless superconducting line across a continent, in principle.


US Patent on Elpipes Issued

The August 5, 2014 published version of my US Patent 8,796,552 is 69 pages. I got essentially everything I wanted in this patent, though I also have a now-published continuation patent and additional unpublished patent cases on advanced elpipe designs pending.


Reply to XCel Energy post by Frank Prager

Facing the realities of deep renewable penetration

I wrote this in response to Frank Prager's post on "Xcel Reveals Winds of Change:"

It was appropriate to give renewables a hall pass to avoid paying their fair share of the load-following and backup costs of the grid for a while, but now I agree it is time to face reality and force renewables to cover their costs. This implies quite a number of ancillary services ranging from frequency control (fast) to load shifting (slow). The slow energy storage options (pumped storage, massive batteries, compressed air energy storage) require large facilities that are much less expensive if implemented in rural areas. Both energy farms and load shifting energy storage will usually be sited quite remotely from cities for economic reasons. Thus transmission has a critical role in making deep penetration of renewables practical, even before considering the importance of locating wind and solar generators.

When one also considers the importance of networking together wind and solar generators in multiple weather systems, it becomes obvious that we need a mix of transmission (to access distant resources) and various forms of energy storage to balance loads from non-dispatchable renewable energy sources. One should also consider the advantages of a wider robust network to share the loads between cities, not just for emergency situations but for routine 2-way power flows. HVDC holds the potential to unlock the potential of a supergrid, to create a free market for electricity over a market area.

HVDC schemes have so far been hamstrung by the redundancy standard: that the grid must survive loss of any single resource, such as a powerline or generator without crashing the grid. It is precisely because HVDC schemes have been proposed one at a time that this limitation has been a problem: so far, the redundancy for every HVDC scheme has had to be via the AC grid, and because of this it has been impossible even to deliver the maximum capacity of current technology HVDC (about 7 GW, equal to the highest capacity Chinese HVDC line), because the AC grid cannot handle simultaneous loss of 7 GW. Although I have been working on the next generation of HVDC power lines, capable to about 30 GW, it is clear to me that before there can ever be a market for a 30 GW powerline, the redundancy question and circuit breakers for HVDC must be solved. On redundancy, this post:

points out that the smallest “unit cell” of the future supergrid comprises an HVDC loop. Such a loop, with circuit breakers in the loop between every set of next neighbor AC/DC converters, is self-redundant, because for any pair of AC/DC converters on the loop, they are connected by two independent lines, the clockwise connection and the counterclockwise connection.


New beginning for Elpipes within Alevo

I have struggled to keep my vision of elpipes moving forward for the past six years (since late 2008). I knew that without patents, I had nothing, so I put a large amount of energy, and most of the money I have spent, on the patents. The first elpipe patent, which has now been granted in the USA(patent #8,796,552), and is in the back-and-forth approval process in Europe and China. Similarly, though only since 2011, I focused on the patents for Ballistic Breakers; those patents are also now on the verge of being granted in the US.

I have recently found the visionary investor I've been seeking, Jostein Eikeland, and  am now in the process of folding my two DC grid-enabling inventions into his company, Alevo. I will continue to head up the development of elpipes and Ballistic Breakers, but now with an R&D budget so that we can move on to development of prototypes. I am very thankful to Jostein for this opportunity.

This announcement was not published until October 12 to respect Jostein's desire for secrecy, and to avoid anything pulling attention away from the launch of our GridBank™ battery modules on October 28.


Article in Natural Gas & Electricity on HVDC loops in Europe

My latest publication is Underground HVDC Supergrid can work in Europe in the March issue of Natural Gas & Electricity, a Wiley publication:

(credit as follows: "Faulkner, Roger W.Natural Gas & Electricity30/8, ©2014 Wiley Periodicals, Inc., a Wiley company.").

This article specifically discusses a European supergrid based on HVDC loops. 

Over the years that I have pursued the vision of a continental scale supergrid, I have always proposed designs based on HVDC loops with multiple terminals. In the beginning I did not yet fully appreciate that loops are intrinsically redundant, as long as there are main loop circuit breakers between neighboring AC/DC converters linked to the main loop. All the currently installed HVDC schemes rely on the AC grid to supply redundancy in case a sudden generator or transmission line failure occurs. It is this fact that sets the maximum capacity that can be carried by an individual line, and at a much lower level than is feasible for the HVDC links per se. 

Creating a true DC grid based on intersecting loops ("meshed grid") requires a DC circuit breaker that can interrupt main loop fault currents, which could go as high as hundreds of GW during a short circuit. To avoid that, I have come to think that superconducting fault current limiters (SCFCLs) are vital in the mix of technologies to protect the DC supergrid. In effect, the SCFCLs protect the circuit breakers by allowing them to be designed for lower (but still very large) fault currents.

The other technology that will be needed for a supergrid in addition to circuit breakers and fault current limiters are flow regulators, which work by adjusting the voltage drop through the regulator. In effect, flow regulators work like throttling valves on a water distribution system, evening out the flow through the various parallel connections of the supergrid. In order to not be lossy, the flow regulator must be hooked up to the AC grid or to energy storage, so that the inline load imposed to create a voltage drop on an HVDC main line is exported to the local AC grid directly or via an intermediate energy buffer storage. (This last bit was not discussed on the Wiley article.)


The elpipe concept can be used to install cables too

My elpipe patent application arguably covers any form of electrical transmission system in which the actual current-carrying power line moves like a train inside a pipeline for purposes of installation, repair, and maintenance.  This mechanism could be used to put subsea cables into pipeline conduits along the US East Coast for example, which is relevant because subsea cable has higher voltage rating and higher power carrying capacity than underground cable designed for overland transport. 

For example, 100 km sections of subsea cable can be unwound off a ship directly into the pipeline conduit. Visualize that the cable is held aloft by small robotic vehicles that carry the cable in to a pipeline conduit; this might look like a long line of robotic army ants carrying the cable in, and then putting it down, but more likely the robotic vehicles will roll on wheels

The same principle could work for superconducting lines, of which there are two different feasible types. Among the type 1 superconductors, magnesium diboride is especially desirable, as it only requires liquid hydrogen for cooling, rather than liquid helium. It is much easier to manufacture type 1 superconductors in great lengths compared to the type 2 HTS (high temperature superconducting) cables, but both are feasible to install by the elpipe methodology, in very long pieces without splices. In both cases, the cable and cryostat would roll into the pipeline, analogously to the way that a subsea cable would be installed.

This generality makes the elpipe patent valuable for installing currently available technology, even before the segmented polymer-insulated designs that I originally envisioned as elpipes are proven.


State of the art from State Grid Corporation of China (SGCC) on Thyristor-based HVDC

source: http://www.sgcc.com.cn/ywlm/mediacenter/inspotlight/10/297984.shtml

I thought this press release from State Grid Corporation of China was excellent, and really laid out their future vision for HVDC upgrades. I have reproduced the cited press release below. I have interspersed my own comments as well, identified clearly by RWF. It is clear from this, I think, that State Grid holds firm to the course of pushing line commutated converters (LCCs) based on thyristors to higher currents and higher voltage. This is not very compatible with the supergrid concept, I think, though all the innovations developed by State Grid will still be useful in a supergrid, regardless of the concept they were pursuing when the innovations were made. The key difference is that a supergrid requires multi-terminal HVDC and bi-directional energy flow; (but not necessarily EVERY energy flow needs to be bi-directional).

China Energy News: China Ready for Large-scale Construction of UHV
Released on:2013-10-23         
    The test run meeting of the Xiangjiaba - Shanghai ±800kV UHV DC project was held in Beijing on 9th November. Deputy Director of Electric Power Department of National Energy Administration, Qin Zhijun pointed out that in spite of large capacity and technological difficulty of UHV DC projects, with independent innovation, SGCC successfully tackled a series of worldwide technological problems through comprehensive and solid scientific research and cooperation. National Energy Administration supports the development of UHV DC technology and hopes that SGCC can summarize its past experience so as to better push forward UHV DC technology.

  Not only the Xiangjiaba – Shanghai UHV DC project, projects including 1000kV Jindongnan-Nanyang-Jingmen UHV AC project, Jinping-Sunan ±800kV UHV DC project, 1000kV Huainan-Zhebei-Shanghai UHV AC project, and Southern Hami-Zhengzhou ±800kV UHV DC project in adjustment as well as the East Shore of Xiluodu -Jinhua ±800kV UHV DC project and 1000kV Zhebei-Fuzhou UHV AC project that are under construction, are the results of scientific innovations as SGCC has tackled down problems that the world is now facing.

RWF: State Grid relies on the AC grid for redundancy
UHV DC realized domestic production

  It is learned that SGCC first invented the 6-inch thyristor and applied it in the Xiangjiaba - Shanghai project. The 800kV, 4500A, 1.8GW thyristor valves that SGCC made updated the world record in voltage, current, and capacity. The DC technology can now transmit in 8GW-level over 200km instead of 3GW-level within 1000km. Meanwhile SGCC created the first UHV converter transformer of the highest voltage and largest capacity but with the same transmission constraints as a 500kV converter transformer.

RWF: not sure what this means "The 800kV, 4500A, 1.8GW thyristor valves that SGCC made updated the world record in voltage, current, and capacity." I understand that SGCC increased the ampacity of the thyristor to 4500 amps by increasing its diameter; at the +/-800kV voltage level (which requires multiple series-connected thyristors), this corresponds to 7.2GW, the current best proven transmission capacity. I do not know what is meant by the "1.8 GW thyristor valves?" This appears to reference the 400kV modules that are used to form the converter. It would be more useful to know the voltage step per thyristor: is it still 8kV as is used by ABB, or have they advanced to the 12kV per thyristor step that was achieved in the USSR before their research was shut down by the collapse of the Soviet Union?
  Experts of the test run said that the technology of the UHV was successful and could be popularized in application. The project has maintained a stable operation since its launch 3 years ago, transmitting 47.3TWh of power in total, which provided a solid foundation for transmitting excessive hydropower from Xiangjiaba power station and the Southwest to other places, especially during summer peak time in 2013 when the machines were running overtime and with overload. The project greatly eased the pressure of power demand from East China such as Jiangsu, Zhejiang and Shanghai that suffered high temperature.

  In technology innovation, SGCC was never satisfied. It accelerated the development of UHV technology on the basis of the stable operation of Xiangjiaba–Shanghai project. Deputy Director of Department of DC Construction, Gao Liying introduced that with self-innovation, the company had another breakthrough in Jinping-Sunan project. The UHV DC system was completely domestically designed and the low-end converter transformer was also domestically researched and developed. China-made converter bushing was applied for the first time. Polar low-end stations also used independently developed UHV converter valves and control software for the first time. DC equipment was supplied by domestic manufacturers in set. All these signified that China was ready for systematic and domestic construction of ±800kV UHV projects.

RWF: Watch out, ABB, Siemens, and Alstom Grid! From SGCC's perspective it might look like the push towards multi-terminal HVDC, and voltage-source converters by the Western "Majors" is more about changing the game to their advantage than anything else. They may be right, but my reasons for advocating a supergrid are not influenced by those considerations.
  In addition, the Southern Hami-Zhengzhou ±800kV UHV DC project to be put into operation at the end of this year and the East Shore of Xiluodu -Jinhua ±800kV UHV DC project under construction have larger transmission capacity, more advanced technology and are more domesticized. They will further validate the advantages of UHV AC transmission with high capacity and high efficiency over long distances.

  Equip China with strong DC technology instead of just large DC capacity  

  “While bringing the economic and social benefits of UHV into play, SGCC also made a breakthrough in the core technology of high-end products based on construction of UHV  projects which helped to realize leapfrog development of manufacturing power transmission equipment. The most representative example is the research and application of UHV converter valve,”said Tang Guangfu, Director of the DC Department of the Institution of Smart Grid Research of SGCC and the general manager of CLP Power Engineering CO., Ltd, Purell, “A sophisticated system based on power electronic devices which combines knowledge of different sciences is difficult to control. To a certain extent, it represents the level in equipment manufacturing as well as scientific and technological innovation ability of a nation. So developing the UHV converter valve with full independent intellectual property rights is a strategic demand to construct the Strong and Smart Grid.”

  It is known that UHV converter valve is the core equipment of a UHV DC project, the electric power equipment that realizes large-capacity electricity transformation. But the manufacturing of the equipment used to be monopolized by multinationals like ABB and Siemens for a long time. In order to tackle this problem, SGCC developed the valve prototype with full independent intellectual property rights with reference to the experience in major DC projects, cooperation and collaboration, and solid scientific research. Now a test platform for converter valve with the highest test parameters in the world has been established.

  The prototype has a rated voltage level of ±800kV, a rated flow of 4500-5000A, and a fault current of 50kA. All these core technical parameters excel similar products from home and abroad while the cost was 20% less than that of the foreign ones. The demonstration devices of the valve has the highest test voltage of 80kV,
RWF: that answers my earlier question. An 80kV test voltage for an individual thyristor could potentially mean 24kV per series-connected thyristor in use (current ABB thyristors are used at 8kV per step; that implies one third as many thyristors! per 400kV converter module. If I have interpreted correctly, that is the biggest bit of news here!).
the highest steady-state DC test current of 6kA and the maximum fault current of 55kA, all representing the highest level in the world. The successful test of the converter valve can save 2 million yuan for each DC project in our country.

RWF: This is huge, potentially. What if Chinese Foreign Aid starts funding 800kV HVDC lines around the world?
  Tang Guangfu pointed out that the research and application of UHV converter valve made China the third country to master the core technology of UHV DC converter valve following Sweden and Germany, which altered the pattern in the international DC market and realized three transformations of China’s DC industry. 
RWF: Mitsubishi is also a technology leader.

Now equipment was not just made in China, but created by China. And the country is now leading in the industry instead of learning from other countries. The industrial pattern has changed from large DC capacity to strong DC technology.

RWF: Congratulations! SGCC can supply the current state of the art highest capacity HVDC line. The highest capacity on one set of towers is a double-circuit overhead powerline based on 800kV with SGCC valves @ 800kV: 7.2 GW/circuit times 2 circuits. This sets a very specific alternative product to compare elpipes against.

I would also like to publically disclose, and thus make this concept non-patentable (if it is not already): 
one can also have elevated, air insulated pipes (busbars that go many kilometers); that must also be considered as an alternative technology.
  Domestic UHV equipment realized mass production

  While continuing making progress in solving the problems in UHV DC technology, the development of UHV AC technology attracts worldwide attention.

  The 1000kV Jingdongnan-Nanyang-Jingmen AC transmission project is the first commercially operated 1000kV line in the world, which was commissioned five years ago. Before that, countries like the former Soviet Union, the United States, Italy and Japan have tried to develop such technology but failed to form mature technology and standards, not to mention system electrical equipment. However, this project conquered worldwide challenges in high voltage, strong current electromagnetism and insulation technology, breaking new records in six aspects including voltage control, external insulation technology, system equipment manufacturing, electromagnetic environment management, construction of demonstration projects, and experimental capability.

  Chen Weijiang, Deputy Director of AC Construction of SGCC, said that the project greatly enhanced China’s  scientific technology in electric power, upgraded power transmission and transformation equipment manufacturing industry, gained bigger voice for China on the international arena in the electrical technology industry, and established China’s leading role in world’s UHV industry.

  On 25th September, 1000kV Huainan-Zhebei-Shanghai UHV AC project was put into operation, establishing a milestone in the world’s UHV history. It is introduced that the project is the first commercially operated double-circuit UHV AC transmission project on same tower, whose transmission capacity per corridor is doubled than single-circuit technology. It represents the highest level in UHV AC transmission technology, equipment manufacturing and engineering application in the world.

  Chen Weijiang introduced that facing the challenges, SGCC organized people from over 100 organizations from the electric power industry and the mechanical industry to tackle a series of worldwide problems in areas of system design, equipment manufacturing, installation, testing and readjustment of the double-circuit UHV AC transmission system on the same tower through domestic research and independent innovation. It can be said that Huainan-Zhebei-Shanghai UHV AC project not only broke new records in UHV AC technology but also upgraded the electric equipment manufacturing industry.

  For example, the project first invented the loaded voltage-regulating UHV transformer and single-column UHV shunt reactor with a rated capacity of 240MW. The manufacturing quality and reliability of domestic UHV equipment has been systematically enhanced, able for mass production. In addition, based on the innovative experience, China has made leapfrog progress in the organization, management, S&T, manufacturing, construction and operation in the transmission and transformation projects, laying a solid foundation for large-scale construction of UHV grids.

  Adhere to independent innovation to command new height in S&T 

  SGCC never stops moving forward and innovating, which is the only way for eternal brightness. The company is now aiming at higher objectives after realizing the system design of  ±800kV UHV DC project and the domestication of overall construction.

  Gao Liying introduced that based on the research results of the ±800kV/5000A UHV converter valve, SGCC also successfully installed the world’s first valve tower prototype with ±1100kV/5000A UHV DC converter valve of independent property rights of China, a remarkable accomplishment in the high-end products of UHV industry. Its operational test was successfully conducted at the same time. This can play as a pillar to the demand from constructing higher-grade UHV DC projects, and enrich and improve the UHV theology.

  It is known that this scientific program carried out a series of scientific researches such as research on steady-state electromagnetic disturbance characteristics of large capacity UHV converter valve and research on upgrading the anti-electromagnetic ability of valve monitoring equipment in unfavorable electromagnetic conditions for the ±1100kV Zhundong-Sichuan UHV DC project. At the same time, the project put forward new design theories such as optimized design of grading and shielding system, light thyristor installation structure, and compacted triggering monitor system.

RWF: I think higher voltage than 800kV in a supergrid is not needed. If we go with the low cost conductor sodium, sealed in high strength alloy shells, then the lowest total cost for conductor + insulator occurs around 400-600kV...more on that below the SGCC document end.
  SGCC Chairman Liu Zhengya also introduced in the recently held International Smart Grid Forum that the transmission capacity for ±1100kV UHV DC technology and equipment could reach 13.75GW with an economic transmission distance of 5000km, providing the foundation for cross-regional, cross-national and cross-continental power transmission lines. With that Africa and the Middle East can be linked together, and there can be a big grid in South America.

  President of IEC, Dr. Klaus Wucherer pointed out resource was distributed unevenly in many countries. Since UHV can reduce the loss in long-distance transmission, it will have a bright future in other places of the world, too. Right now, China is leading in the technology of UHV transmission. The UHV AC voltage in China is promoted in the world as the international standard.  

  Source: China Energy News


Scientific American Article that disparages the supergrid

For now, this is a place-holder. Below is a letter by Roy Morrison about the Scientific American article. I will write my own letter to the editor later, and substitute/modify the text below from Roy.

Prospects for Continental Grids

Vacil Smil's prediction (Scientific American Jan. 2014) of a long and painfully slow rise of solar and wind, offering little in way of timely greenhouse gas reduction, is an accurate business as usual projection.

But facing global ecological catastrophe means these are not usual times. In fact, Smil correctly indicates that continental scale efficient renewable energy grids, that are inherently self-balancing, represents a potential game changer1Alas, Smil says, there is sometimes opposition to power line construction, and leaves it at that. This is opposition that can be and must be circumvented for us to gain the huge economic benefits of continental grids. 

I have been working on the idea of putting high capacity HVDC lines underground for many years; the elpipe is but one example of a high capacity HVDC underground electricity pipeline (though I am convinced it is the most practical approach). I am of course pushing for my solution, but there are at least three other examples of technologies that move the supergrid underground:

  • Gas-insulated lines;
  • High temperature superconducting (HTS) lines (cooled by liquid nitrogen);
  • Type 1 superconducting lines, cooled with liquid helium or liquid hydrogen in a few cases (notably, magnesium diboride).
Each of these alternatives has flaws that elpipes do not, as is discussed elsewhere in my blog.

 Moving the main links of a continental grid underground would overcome the opposition (most of it, anyhow) to the new powerlines needed for a continental-scale supergrid. There is a pathway forward to continental scale efficient renewable grids and green house gas reduction before it is too late.

1See Gregor Czisch (2010). “Scenarios for a Future Electricity Supply”. The Institution of Engineering and Technology, ISBN 978-84919-156-2; Original German language dissertation is available as a free download from Kassel University (http://www.agenda21-treffpunkt.de/doku/sign.php?sg=Czisch-2006).

I also found this excellent letter about Smil's SA article by Doug MacKenzie, posted online on his blog:


Eurocentric Treatment of Supergrid Roll-Out Strategy

I submitted an article titled "Underground Multi-Terminal HVDC Supergrid in Europe"
for publication in the Wiley trade magazine Natural Gas & Electricity (manuscript submitted December 18, 2013). With each article, I try to introduce a new concept, and in this case I look at the case for HVDC loops as the unit cells of a European Supergrid, with special reference to Germany:

I see similar possibilities within single states in the US; especially California or Texas. This previous post explains why I think that HVDC loops are the natural "unit cells" of a supergrid. That is a convenient fact, because it means that portions of the supergrid that lie completely within one political jurisdiction can also be meaningful projects in their own right; not necessarily dependent on the entire continental scale supergrid being built.


Elpipe patent will be granted in the US

The national phase patent applications have been working through patent offices around the world. I am pleased that I will get 20 claims in the US, as seen in this modified US patent application on elpipes. As is customary, there was some narrowing of claim 1; I had to add wheels to the minimum definition of elpipes in claim 1:

1. A modular high-voltage direct current electric power transmission system, comprising:
an elongated containment system, the conduit;
a plurality of elongated generally annular rigid primary conductors, which comprise the central portion of the segment modules, generally aligned end-to-end within the containment system;
a plurality of splice transition conductors which are connected to each end of the primary conductors;
a generally annular primary insulator surrounding each of the primary conductors;
a plurality of compliant conductive electrical splice members, one splice member located between and electrically coupled to opposed ends of the primary conductors, to accomplish electrical continuity while allowing for axial misalignment between such conductors;
a plurality of splice insulators, one such a splice insulator surrounding each splice member; and
further comprising wheels located between the primary insulator and the containment system.

Here is the actual text of the written office action (page 8):

3. Claims 1-20 are allowed
    The prior art taken either in singularity or in combination fails to anticipate or fairly suggest the limitations of the independent claim 1...

I have filed plenty of patents before, and I never had such a letter approving all my claims. As claim 1 reads, my invention applies to any kind of flexible powerline that can move like a train inside a pipeline conduit. That means that 100 km sections of MIND cable can be unwound off a ship directly into the conduit; if such a cable is transported by robots that carry the cable, that is an embodiment of my invention. To visualize how that will work...think army ants with the cable on their backs. The installation and rapid repair method works for superconducting lines, though the minimum bend radius for different superconductors varies a lot. 

The patent will publish in three months, and I intend to use that time to ready a crowd-source investment strategy to get me to the first 100kV prototype, with a complete design for an 800kV elpipe. Right now, I am on both GUST and Wefunder. In general, I am looking for a "qualified investor" under SEC rules to put in at least $25k at a very good valuation. When that happens, I can then be listed on Wefunder, where I hope to raise $1 million via crowdsource funding to get me to the first 100kV prototype and finish the international patents. This prototype will then help a more conservative set of investors to come in for $35 million to build an 800kV working elpipe.


I was in the ten out of 200 applicants to present at the Silicon Valley Innovation and Entrepreneurship Forum.

I was one of ten presenters to the full SVIEF conference (chosen from a pool of 200 applicants). Al Gore and Steve Wozniak were headliner speakers. I spoke about elpipes (primarily) and HVDC Ballistic Breakers (somewhat) as enabling technologies for a supergrid (Electric Pipeline Corporation).

Here is my presentation. I will post a video when I receive it from the conference organizers.

I had a spirited exchange with the judges; at one point I cut one of them off who was blathering on with way out of date information on the Tesla/Edison "War of the Currents" that has not been true since 1960!
In this talk, I spoke from the heart about something I care a lot about. And unlike in the US, the Chinese are not averse to big, world-changing technologies. I am hoping they decide to do it, and that I get to be a part of it. In fact I'd like to lead the development team. As in the US, though, the government must lead on something this big.

EPC also got a free booth at SVIEF 2013; In the picture below, that is me (Roger Faulkner) on the right, my Dr. Imayavaramban Munuswamy on the left, and Bryan Steele of USgrid.us (who came to help out) in the middle.

The SVIEF 2013 occurred November 2 in Santa Clara. I got my booth for free (I won it) and I just learned October 29 that I'd be one of 10 entrepreneurs  to present to the whole conference. 

This quote puts the HVDC opportunity in perspective:
> If every system that has been announced for commissioning between now and 2020 is actually built, the cumulative global capital requirements for HVDC systems would be around $217 billion, according to Navigant Research.
Of the officially announced HVDC budgets and schedules, Navigant reckons only about half will be built, leading it to conclude in a 2012 report that there is an 80 per cent probability that the cumulative spending for HVDC systems between 2012 and 2020 will range between $110 billion and $120 billion.

I have something really new, but made up of well-proven pieces. Because of that, elpipes can be developed and implemented quickly. They are patent pending in China, US, EU, India, Canada, and Malaysia. I need to find investment to complete the patent process, and that creates an opportunity for a relatively small investment to create a very valuable position. 

Elpipes are
 enablers of a supergrid, and a supergrid is the fastest feasible way to decarbonize the Chinese economy. We in the West have lost our taste for big technology solutions; this is now the mantle for China to take forward. I am working with a group that sponsored the "World Culture Forum" in Taihu; I do not understand Chinese politics, but I do know that two politburo members with strong environmental credentials were behind the World Culture Forum, and are now evaluating my proposal
 to move China towards a supergrid
. It is vital for the world that China leads in the development of a Eurasian Supergrid.

The construction of a Eurasian supergrid will logically start either in China, India,
 the EU. Among all the entities in the world I can think of to develop elpipes, I have no doubt that it c
 be accomplished fastest in China. 

There is a backstory to this. Since I was a teenager, I have thought about underground electric pipelines; I got the basic idea of a supergrid from R. Buckminster Fuller when I was a teenager, and I thought of elpipes then, more than 30 years ago. When I studied physics I learned how to calculate the mass of the conductor needed. A lot more conductor is used in an elpipe than a set of overhead lines (from 3-18 times more than equal capacity overhead lines), but not more volume of conductor than will fit comfortably inside a typical gas pipeline. My invention is a high voltage current carrying train, in which the cars of the train are rigid bus pipes, linked through flexible couplings much like rail cars. The track is the inside surface of the pipeline which is just like a gas pipeline with no elbows or tight bends. 

I decided to act on this idea in late 2008, after Obama was elected. I applied in the first round of the ARPA-E program and three more times since then. I was first runner up in the 2009 Ignite Clean Energy Business Plan Competition, then spent a year with my partner Ron Todd making venture capital pitches until he quit in 2010 after I failed to get a deal with ABB (it was a close call, though). 

In 2011-2012 I shifted my focus to medium voltage DC applications of Ballistic Breakers, which could be important enabling technologies for DC microgrids. My heart was never really in that, though. I am so glad to have had another chance to pitch elpipes and HVDC Ballistic Breakers.

The most important application for Ballistic Breakers is in enabling a multi-terminal HVDC supergrid. HVDC Ballistic Breakers will be less expensive than ABB's new HVDC circuit breaker. The combination of elpipes for high capacity bulk transfer and Ballistic Breakers as low cost HVDC circuit breakers are powerfully enabling for a future HVDC supergrid.