3/12/18

Why Norway should become the battery of Europe


This is an article that I am working on with my friend Tord Eide and a Norwegian professor from NTNU. Hopefully it will go into a Norwegian magazine. There is also a second article we've are working on that would go into a newspaper. If anyone reading this Article Is willing to help create the maps that I refer to below,Please contact me…Roger



Why Norway should become the battery of Europe

A debate rages at this very moment about whether Norway should connect strongly to the European electrical grid or use its abundant hydropower resources just for  Norwegians. We argue that using Norway's vast hydropower resources as the battery of Europe would make a vital contribution to the decarbonization of the world's future energy economy. This does not require Norway to sell its energy supply, but simply allow existing hydropower reservoirs to function as reversible batteries. This is Norway’s chance to think in scale and actually be a major contributor to affect the global climate. 

In order to actually become the battery of Europe, Norway needs a lot better electrical connection to the rest of Europe. The best way to accomplish such a connection is with a supergrid. A supergrid is a continental scale high-voltage DC (HVDC) grid, and this could be accomplished either with overhead powerlines or underground powerlines. Underground cables however are not up to the task because of their limited transfer capability per cable. This limitation is not likely to ever be overcome, because it is based on the simple fact that cables have to wrap on a reel in order to be transportable, and that limits the maximum diameter of both conductor and insulation per cable.

With presently proven technology we would have to build a lot of of new overhead power lines to make a European supergrid; this is precisely why the southern part of Germany is not strongly connected electrically to the northern part of Germany at present; large new overhead power lines are simply politically impossible in Europe today. 

Underground cables are not a solution either, as their capacity is typically limited to  about one gigawatt (1.0 GW) per cable. New technology is needed, capable of carrying more than 10 GW underground. 

There are four developmental technologies that could work for building an underground supergrid in Europe including two different flavors of superconducting lines (one which needs to be cooled with liquid hydrogen or helium, the other which may be cooled with liquid nitrogen), gas insulated lines (GIL), and the elpipe (the newest technology in this list). Figuring out which of these underground options is the best solution for creating a European supergrid should be a research priority in Europe, but that has not been the case. 

So far, the research has been driven by commercial entities with products they want to sell. Siemens has maintained a research program looking at GIL transmission of HVDC power, as well as AC, and ABB he was also active in this area up until 1999, when they sold their technology to US corporation AZZ.  ABB also has an active program for  HVDC cables.

Many companies are pursuing superconducting powerlines (one example is American Superconductor), and there have also been many research reports and studies from national labs and other similar entities looking at superconducting powerlines as well. Superconducting power lines of any design suffer from flaws that are uniquely a function of superconductivity per se. These  faults taken together are fatal to the practicality of a wide-ranging superconducting supergrid:
Transitioning to a non-superconducting state can be instantaneous and can be triggered by a current that  is over a limit even for a microsecond. This can lead to a catastrophic plasma explosion if the line is carrying a lot of current.
 the maximum practical voltage for a superconducting DC power line is around 130,000 V due to the difficulty of insulating under cryogenic conditions.  this is an unsuitably low voltage for conventional HVDC, so in a sense superconducting lines don't play well with the existing technologies.
Superconducting lines have no damping properties.  that means that resonances do not damp out. This is a critical threat to reliability.
every junction between the superconducting lines and the conventional grid is a high maintenance and difficult installation, the failure of any one of which could bring down the grid. Keeping the number of such junctions to a minimum is absolutely required.
It is very difficult to maintain cryogenic conditions reliably, and at all times (which might include times of national disasters such as widespread flooding or earthquakes).

Superconducting powerlines, which have often been proposed for long distance power transmission, are far from being practical at this point, and the other major industry sponsored powerline concept that could have adequate power transfer capability for a supergrid (GIL), has the fatal flaw of relying on an incredibly potent and practically immortal greenhouse gas for insulation, sulfur hexafluoride. Both superconducting powerlines and GIL powerlines suffer from poor repairability in terms of the time it would take to repair a major fault. (When something as important as a 10+ GW powerline fails, it is critical to be able to repair it in hours, not days.) Failure modes for both GIL  and superconducting lines are very difficult, potentially resulting in many days long outages.

The elpipe has been successfully patented around the world, in spite of the fact that one has never been built.   This happened because the elpipe is so firmly based on well-established physics, that the patent examiners admitted it as new invention without ever having had a working model built. This is quite an achievement in itself, and it is a testament to the simplicity of the idea. It is a shame that such an innovative technology has not been able to find funding.

The elpipe has unique features related to repairability. Such technology can be utilized to build an underground European supergrid, and a European supergrid is absolutely required in order to have a renewable energy future for Europe.

Even if there were no bottlenecks in transmission, the installed hydroelectric power capacity of Norway (~30 GW) is not large enough to truly serve as the battery of Europe. Something on the order of 100 GW of energy storage power capacity will be required to allow for 100% renewable energy generation in the mix for Europe. However, if more turbines were installed, the energy storage in existing Norwegian reservoirs (80 TWh) could make a significant contribution to solve the European challenge. A proposal from the research center CEDREN described a step towards becoming the battery of Europe in the form of 20 GW of new pumped storage turbines to be installed on existing Norwegian reservoirs, combined with several new power lines and subsea power cables to European power nodes. These new power lines would cause most of the environmental and aesthetic damage to Norway, and would represent about half of the total cost. We recognize and understand the resistance of Norwegians to these new powerlines; indeed similar resistance throughout Europe to overhead power lines makes such schemes politically impossible. 

We propose a much larger concept for Norway becoming the battery of Europe than any prior proposal, based on HVDC loops, enabled by elpipes, and capable of exchanging much more stored energy with Europe than has previously been contemplated. This scheme however will produce far less environmental and aesthetic harm because it uses underground electric connections (elpipes and cables). We must get beyond the paradigm that power moves through power lines from node to node; continuing in that paradigm would mean that for Norway to become the battery of Europe, we would need at least 20 new power lines connecting us to our neighbors. Most such interconnecting power lines will become outmoded (stranded assets) in the future scenario of having a European supergrid.

If one compares the environmental impact and cost of installing more turbines on existing reservoirs to the environmental impact and cost of building new energy storage facilities, it is clear it would be far more desirable environmentally to use the existing reservoirs rather than flooding new valleys (in the case of hydroelectric energy storage), or mining the resources required for manufacturing and installation of batteries (for electrochemical energy storage).

Building new hydroelectric power capacity based on installing new reversible turbines on existing Norwegian reservoirs would create additional storage capacity without having to build any new reservoirs. The main unavoidable environmental impact for this scheme would be that the levels of the reservoirs would be changing more quickly than they are today. The tunnels, turbines and generators that would be required could all be installed underground. 


In order for Norwegian power to truly work as the battery of Europe, the power must be deliverable, and power flow must be controllable at many different connected power nodes inside Europe, with millisecond level control of power flow into or out of each node. None of the currently proposed schemes, such as Figure 1, taken from the Nordic grid development plan 2014 which all involve point-to-point powerlines, would accomplish this. 

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