I recently stumbled upon some High Voltage Direct Current (HVDC) technology that seems promising to me for long distance transmission. It is not existing technology; it is a detailed proposal with no prototype and not even a computer simulation behind it. Nonetheless it looks like a less expensive and more environmentally friendly way to move large amounts of electricity over long distances — well worth further exploration.

The basic idea, elpipes, as developed by Roger Faulkner is to place HVDC lines inside insulated pipes, which can then be buried underground or placed just above ground rather than raised on transmission lines. No EMF (not that the evidence for EMF damage, especially from DC lines is not weak). No chance of living creatures bridging uninsulated lines and frying themselves along with expensive transmission capacity.

Unlike other forms of underground HVDC, it can reach high capacity with only passive cooling for up to 12 GW underground, and reach up 25 GW above ground. Beyond that active cooling is needed, but less than with other systems. No gas insulation. It uses simple aluminum wire for transmission, making up for aluminum’s lower electrical capability per cubic foot by using more metal.

Overall the cost would be lower per mile than any other form of underground DC transmission, and (Faulkner claims) lower in many cases than overhead transmission. Also it is claimed that elpipes require less maintenance, and are far easier to maintain other forms of underground electricity. (Maintenance costs are one well known weakness of underground transmission.)

In terms of impact, elpipes need a corridor with about same characteristics as a natural gas pipeline — up to 60 feet total. These don’t need to be kept totally clear, but clear of trees and tall or moderate shrubs. Run along highways or railroad right of ways, and existing logging roads the impact would be zero. Run through the desert, plains or meadowlands they could be buried underground and most (though not all) of the natural plant life allowed to grow back over them. Run through forests and woods (other than under logging roads), there would be impact because of that 60 foot tree-free (but not grass or low-shrub free) strip. But it would be less than any other form of HVDC transmission. And there is no Kilowatt Fairy, no BTU Bunny. Right now we get half our electricity from coal. If replacing that with something far less polluting requires long distance transmission, it is unreasonable to hold that to a zero impact standard.

Of course, something that only exists on paper always looks cheaper, simpler and cleaner than a real world product. See Admiral Hyman Rickover’s 1953 testimony on real and academic reactors [PDF]. But papers [sub. req.] on elpipes have been published [PDF] in a variety of professional journals and presented at professional conferences. Rodger Faulkner appears to have strong real-world professional credentials. Without guarantees, I strongly suggest this technology is worth further investigation.

If I were an entrepreneurial billionaire, this is what I’d do:

  • First, I’d get a qualified in-house employee to do a quick check for obvious flaws.
  • If it passed that, I’d get someone to do a rigorous preliminary check for non-obvious flaws — hiring a consultant if necessary.
  • If it passed both preliminary checks I’d put together a team to do a full check, consulting Mr. Faulkner, and running a rigorous simulation if appropriate.
  • If the concept passed that test, I’d put together a business plan, and fund a prototype.

I have some feel for transmission concepts, and this definitely merits investigation. It is the nature of innovation that not everything meriting investigation is worth building, but I suspect this will be.

Faulkner has also proposed a passive arc-free breaker whose merits [sub. req.] I won’t judge, not even on a tentative and preliminary basis.