Today is the ninth post in this Monday series of subjects covered during my summer 2014 interview of Bill Reinert, recently retired energy engineer for Toyota who played a key role in the development of the Prius and then assumed the role of future transportation planning of alternative-fueled vehicles at Toyota. See his full bio here. –Kay M.
Electric transformer near Dundurn, Saskatchewan. By Trekphiler. Wikipedia.
K.M.: What is the future of the electrical grid? How can we integrate renewables into it in a way that makes the most sense? Please comment on Germany’s renewable-grid situation, and, also, my town of Boulder, Colorado, which is planning an electrical municipal system with the goal of helping reduce greenhouse emissions.
Reinert: The problems with Germany’s power system and the transition to renewables are mostly political and in many ways likely point to Boulder’s future.
For decades the Greens have had a disproportionate role in Germany’s energy future. After Fukushima there was quite a bit of hysteria about nuclear energy. Merkel was in political trouble, made a deal with the Greens, and energiewende was born. The targets are lofty, 100% renewables and elimination of all nuclear plants. The trouble is energiewende targets were set by politicians, NGOs, and Academics with little or no industry experience and when expert opinion was offered it was largely ignored.
The problem is and remains the intermittency of renewables. Given current technology about 30% renewables is about the maximum any portfolio can adequately handle. Much beyond that and you need to match renewables watt for watt with spinning reserves. And this is best case. In harsh climates the maximum renewable penetration is much smaller. It’s not how many windmills you build, or how many solar plants come on line, what matters is how many usable watts are produced over the year. Through that lens the price of renewables is quite high. The figures we see quoted about the installed costs coming down are misleading. These costs generally do not include intermittency nor do they include the costs of spinning reserves to span the intermittency. And they don’t include the costs of non-dispatchable power.
To get around the intermittency issue without resorting to additional fossil plants all manor of energy storage or power matching schemes are being tried. Most don’t work and all result in a near doubling of costs for each project, costs that are eventually passed on to the rate payer. You already see the results writ large in California and German electricity prices. In both cases the idea that regulation would spur technology has resulted in skyrocketing utility rates. For instance our electric rates while in Southern California were seven times what our rates in Colorado are. Still the mandates remain.
Grid energy storage is traditionally pumped hydro or compressed air, both geographically and geologically limited. So now the regulators have moved on to schemes that are both far more expensive and technically challenged. Converting non-dispatchable power to hydrogen in a electrolyzers and then back again to power in a fuel cell ignores the cost and market readiness of both technologies. Grid energy storage in batteries may work with lead acid batteries in small scale in remote areas with no alternatives (think Galápagos Islands), but are cost prohibitive in larger scale applications. Notice I wrote lead acid, not Li Ion batteries and not from the “Giga Hype” factory. Li cannot match lead acid in costs nor in cycle life. The fact that Solar City uses Tesla batteries is due to marketing, not sound technical decisions.
So now on to the more ethereal approaches:
Reusing batteries from EVs once they’re no longer useful for propulsion remains quite a popular notion. While it sounds good, the devil is in the details. Battery pack failure results when one or more individual cells degrade to a greater extent than the remaining cells. So one must recover the packs, measure all the cells and build new packs with matched cells. The costs are nearly the same as building a new pack only this one has a much shorter cycle life. And this assumes adequate resources of used cells in similar configuration. Neither of these requirements are likely to be met any time soon.
There’s all manner of Vehicle to Grid (V2G) ideas being hatched. The University of Delaware is perhaps the world’s leader in these applications. Unfortunately there are challenges both technical and consumer driven. From a technical point of view, V2G assumes a EV penetration that may never exist. And vehicles, unlike power plants, are widely distributed. For this approach to even have a chance of working all of the EVs in a particular region would need to be aggregated and controlled as a single unit. And even if you get through the dispatch issues, you’re still left with the cycle life issues. Individual revenue from these schemes amounts to a few hundred dollars a year, hardly a financial incentive to structure one’s mobility around grid concerns. Even off peak charging isn’t wildly successful. Financial incentives thus far are not a very successful trade off for individual mobility.
Eventually we come to the “Smart Grid”, which I place in quotes as no one can tell you what it really is and why you’d want it. There are some apparent advantages such as elimination of meter readers -and- some day in the future self healing grids. But I suspect the real benefit of the smart grid is using real time pricing to manage consumer behavior to match power availability as opposed to the current mode of matching power production to consumer needs. And where the smart grid has been used for real time pricing it’s been wildly unpopular as electric bills double or more.
So now, today, you can easily see that if you ignore natural gas peaking plants and if you don’t have sufficient nuclear in the grid mix additional renewables mean increased emissions from fossil plants left in spinning reserve.
For all the reasons above it’s hard to see a transition to a renewable grid and still keep a hub and spoke generation and distribution model. With our current model solar means vast plants in our fragile desert ecosystems, areas where water for cooling towers is nearly nonexistent. Wind means giant plants, generally in migratory flyways. Both require significant maintenance and suffer large efficiency losses when the power is distributed over large distances.
So perhaps a new model, a distributed system, with many smaller interconnected plants is the answer. In the beginning these small plants could be combined cycle natural gas. Two-way distribution in urban areas would allow roof top solar to become effective as a true grid participant as opposed to the relative nuisance it is for today’s utilities and grids. Eventually high temperature fuel cells running on waste methane from landfills and waste water treatment plants could factor into the grid. Renewables could then penetrate not from a mandated percentage but rather a cost effective basis.
Once the scale is reduced, hopefully more storage options will emerge. I think phase change materials, taking advantage of latent heat, may come into play. They’re already doing that with solar thermal plants, storing excess energy in molten salts until it’s needed.
This won’t come easy nor will it happen over night. Utilities will fight tooth and nail to maintain status quo, thus you can see Xcel contracting with large solar plants in southern Colorado, and vast wind farms in Wyoming, while at the same time reducing their rooftop solar program. NIMBY will take on a whole new meaning as community scale power plants are proposed. And distributed resources aren’t appropriate everywhere. For instance it would be nearly impossible to build small scale power plants in New York City.
What likely will happen first is history will repeat itself. Like today, the rush to renewables under President Carter was driven by mandates and supported by subsidies. It was a house of cards that couldn’t stand in economic winds. And when the politics changed and the subsidies evaporated, the house collapsed. Only a handful of strong companies, those with a exit strategy survived. Both in the U.S. and in the E.U. we are seeing a growing populist conservative movement emerge. Even with liberal leaders, conservative legislatures can eventually put paid to subsidies for non competitive approaches. Of course the renewables industry will once again shrink, but not to the same level as post-Carter. This time we have more players with realistic business plans. So the remainder will be stronger and growth will begin again.
It’s a stair step process and no matter how badly the regulators and NGOs want at least straight line growth or even exponential growth, under the current approaches they’re unlikely to achieve their goals.
To see last week’s interview subject on the future of renewables, click here.
Coming next week will be Reinert’s comments on the methods used to power cars: electric, CNG, fuel cell, and hybrid.