Thursday, November 13, 2008
Why Not More Pumped Renewable Hydro?
Having built systems in California during the rolling blackouts of the dotcom and having a civil engineering background has given me some unique insight into how many factors shape the way energy is priced. Obviously supply and demand are the utlimate factors in pricing of anything, especially a commodity. However the nature of electricity itself and the fact that it essentially cannot be stored in its 'native' form presents it as the most unique of commodities as well as one of the most in demand for civilization.
With so much emphasis on clean power in the new administration I'm writing this blog as a general question as to why pumped-storage hydroelectricity isn't one of the more mainstream staples of this conversation. Now it's not as if this is some new great idea as my power company, Dominion, actually owns and operates the largest one of these in the world. Rather than regale you with stories of piezometric head understand that this is one method of storing electricity in another form of energy which is potential energy provided by one of the few energy sources that is constant, gravity.
There are other storage mechanisms being devised that have tremendous potential and with enough R&D I believe one or some will come to fruition but when? We can transport hydrogen made from this process if necessary by pipeline or even by trucks powered by the very hydrogen they transport and while most areas have enough sun to produce their own who would actually have the faith to wait for this energy utopia to materialize?
Given that one of the real challenges of all of this new energy generation like wind, solar, tidal, geothermal, etc. is actually how we can get it from place to place so that it can scale practically for the consumers who need it. The problem with all of these is that while with observation we can tell where they perform best we do not control when they produce.
This 'phenomenon', if you will, is really how you find the inside trick of how folks like Duke Power, Southern Company and Enron were the primary beneficiaries of the 'power crisis' in California in the 2000-2001 period when I was living there and building software used by PG&E, Intel and others. The game is essentially that energy is easily manipulated because it cannot be stored and hours of peak demand can be forecast while supply cannot as it is simply finite.
The 'trick' I mentioned is simple and it involves purchasing megawatts in the middle of the night for a dollar and putting them 'on the wire' from California to Nevada to Oregon and back again around noontime on a hot day where the price jumped to over $20,000 per megawatt due to supply and demand. Gray Davis who was replaced in a special election by the Governator himself, Arnold Schwarzenegger, original sin was allowing these electric companies to negotiate a 'cap' allowing the California ISO (Independent System Operator) of the power grid to purchase megawatts under $1,400 but not getting the cheap power benefits.
This shell game of course distracted from the real problem and that is that there was insufficient power to meet demand....period. As an aside it was funny to me that once our software product had achieved the ability to paint this dynamic picture for our cusomters on a daily basis (Enron was a customer and investor) they seemed to lose interest allmost immediately. Before I get off on a rant here I will make my closing argument. The main profiter of the California Power Crisis was the city of Los Angeles who operates pumped hydroelectric storage.
The magic here is being able to run the electric pumps that move the 'fuel', in this case just water, from a lower elevation reservoir into one at a higher elevation. Not surprisingly this can be discharged at will and using its 'head', generate electricity through a turbine like those found in a hydroelectric dam. Now here comes the beginning of my simple premise....the pumping of that water to the upper reservoir takes around 80% of the power that is generated by the same volume's downfall through the turbine. Now it doesn't take a genius or even a civil engineer to understand that this system could be not only used to store the energy from other renewable sources by letting those run pumps when active but can also be the ONE clean source of electricity that can be turned on and off at will as needed.
So while I'm trying to make the case for a clean energy that has few drawbacks in my opinion I also am making a point about how to accomplish something like a new energy program consisting of many more of these sites across the country using another asset of ours that goes largely untapped and that is our digitized geography from USGS and NGA (formerly NIMA).
Bear with me for a second while I tie all of this together. You see we have digitized knowledge of one sort or another that can be brought together in a cohesive set that represents knowledge by which we can extract the appropriate locations that at least in elevation support the needed difference while being located close enough to existing water sources to prime the system and more importantly keep it primed in arid climates. Finally, it makes sense to me to build these upper and lower reservoirs in a series. The lower would simply be two vessels, one for induction to the pump system and one for egress through what could literally be a number of channels that at the bottom flowed out through a single port although powering different generators. It again isn't rocket science to see that with a 1/5 total output differential that the channels in this series could be run in a mode balanced with other sources like other renewables or even traditional fossil to make supply exactly what is needed for the area served in nearly a self sustaining fashion.
These systems would not be huge projects that need be located close to consumers as in the aforementioned one in Virginia. Due to the limiting number of sites where you could build such systems and maintain them with proximity to consumers given the aforementioned transmission efficiency issues these would instead be smaller systems disguised by forest and consisting not of Niagra Falls sized head serving thousands of acres of water but would run the length of more broad plateaus where channels could be bored for proper acceleration to generate power and proper storage much further down the flow line as shown here:
This obviously would work underground as well and yield a less lossy version of the system in terms of evaporation in areid climes.
At the end of the day what I'm proposing is really to use knowledge we already have of things that work and putting supercomputers to work for something useful where can at least generate a set of data that can be sliced and diced by other data that will allow us to rank said sights with plausibility amongst a host of criteria. Good news unlike other hydroelectric is that there is no discharge into the environment and with proper forestation would only be an eyesore from the air. The only environmental drawback would be the initial and continuing priming of the system from nearby water sources.
This is the beginning of a call for us to demand use of data and processing power we have to assemble large sets of usable output....not that supercolliders are not useful but this type of energy is ready to go now.