Monday, December 06, 2004

The Electric Utility of the Future

by Michael J. Osborne

I came to Austin Energy to write a long-term comprehensive energy plan for the City of Austin over two years ago. That plan, now published as Silver in the Mine, is available on the Denver DOE Web site. The book is available at Amazon.com. The opinions in that book and this article do not represent the formal policies of the City of Austin, The State of Texas, DOE, or Austin Energy.

As part of a joint agreement with the DOE, the State of Texas Energy Conservation Office, and the City of Austin, called the “Community of the Future Initiative”, I was tasked with writing a comprehensive energy plan that minimized the negative impacts of energy use. I was to include all of the sectors- buildings, electric, and transportation

Obviously, to minimize the negative impact of energy use, you must use an energy source that doesn’t pollute, is available somewhat locally or regionally, and does not need to be protected by a large military investment. Ideally, it should be sustainable. Given that Texas is number one or two in almost every renewable energy category, the answer for Texans is easy.

As I began to look at realistic de-carbonization transition scenarios, one thing became clear. There is entirely too much duplication of investment in the stationary generation sector and the transportation sectors. When the University of Texas plays football, there is more generation potential sitting idle in the parking lot than in all the generation we have at Austin Energy. (approximately 3.1 GW)

And, there is entirely too much range between our electric peak on a hot summer afternoon and our electric load valley on a pleasant winter evening.

The Unified Energy System

This led me to the conclusion that the Electric Utility of the Future must be part of a Unified Energy System. This conclusion is more born of necessity than ideology. Here is one example. If Austin Energy contracts with wind developers, increasing its wind fraction substantially and thus taking advantage of the good value that wind provides, we will be faced with having to back off base load coal and nuclear generation during our wintertime load valleys.

To avoid this scheduling dilemma, we must either sell our wind power at night at a substantial discount, or we must back down on our base load units. Neither choice makes economic sense.

So we must come up with another strategy. We could increase the nighttime load and/or we could store the energy as compressed air or pumped hydro.

We can increase that nighttime load with a broad portfolio of electrical appliances and schemes. Freezers might freeze ice for cooling the next day; timers might heat water at three in the morning for morning showers. However, the largest potential market to penetrate is the transportation sector.

Simply put then, if an electric utility intends to increase its share of renewable energy using wind energy, it may very well need to charge a large fleet of electric vehicles and other transportation devices. In Austin, the transportation fuel market and the electric KWh market are roughly equal in size. If we could penetrate 20% of the transportation market, we could increase our wind fraction by perhaps 20%. Given that our prices for this wind energy are better than any other generation option, this makes good economic sense. The environmental appeal is obvious and these KWhs would be sold at our green rate.

But what kind of transportation appliance do we want?

The answer is, all kinds of appliances. We want electric bikes, Segways, small neighborhood vehicles, all-electric sports cars, all-electric mini SUVs, and ultimately, a broad catalogue of plug in hybrids.

The cost of electric fuel is seemingly expensive. At 3400 BTUs/KWh and at 8 cents KWh, a gallon of electric gas (120,000 BTUs) is $2.80. But, the electric motor drive is perhaps 80% efficient. A standard internal combustion engine may be 15 % efficient over its driving ranges. Comparing a $2.00 gallon of gas in a 15 % efficient system to $2.80 electric gallon of gas in an 80% efficient system yields another cost figure altogether. Now, the electric gallon of gas is more like ¼ the cost or about 50 cents when compared to $2.00 gasoline.

This comports well with the experience of an Austin Energy executive. He drives an all- electric Geo that gets about four miles to the KWh. That is about 2 cents a mile at 8 cents/KWh. A small standard car that gets 25 miles to the gallon costs about 8 cents a mile.(at $2.00/gallon). However, when you add battery replacement costs, driving costs jump to more than 8 cents a mile and the electric gallon of gas is now roughly equal to the real gallon of gas. (Obviously, taxes are not in this analysis nor is the maintenance on the ICE drive chain).

Even if we sell our KWhs at a deep discount (2 cents/KWh) to our transportation customers to maximize our nighttime off peak load, the storage cost is still the lion’s share of the driving cost.

So, unless battery costs are substantially reduced, it is clear that smaller electric vehicles and other transportation devices, which reduce these battery component costs, enjoy a cost advantage over gasoline powered vehicles of equal size.

Another way to store the energy would be in the form of hydrogen. We can take our nighttime wind energy and run electrolyzers which produce hydrogen and oxygen.

It takes about 50 KWhs to produce a gallon of gasoline equivalent of hydrogen. At a night time deep discount rate of 2 cents/KWh, that produces $1.00 gasoline. When you amortize the costs of the electrolysis equipment, the number jumps another 40 cents. Stuart Energy’s numbers, which include compression, are closer to $2.00. So, 2 cent wind can produce $2.00 gallon of gasoline equivalent hydrogen.

From our perspective then, I see the optimum vehicle for electrifying the transportation sector and increasing the renewable fraction of utilities to be a Hydrogen Fueled Internal Combustion Plug in Hybrid. Ford’s Model U is a good first step in that direction. However, the Model U does not yet have the plug in feature. Ideally, I would like to see it have most of the advanced features envisioned in Amory Lovin’s Hypercar.

We would like a vehicle that has perhaps 5 KWhs of storage, thus giving the car an all-electric range of 20 miles. Battery and driving costs are thus minimized. Such a plug hybrid could run on hydrogen or a variety of sustainable fuels.

Once we have made substantial inroads into electrifying the transportation sector and we are using the storage in those vehicles to allow us to buy more clean wind power, we will be able to consider using these same vehicles as distributed generation devices to help us meet peak demand and intermittent resource shortfalls. Our transportation fleet then becomes a vital part of the overall system. All of those cars at Memorial Stadium would actually then be able to partially power the rest of the city, if the need were to arise.

This would complete the unification of the stationary electric generation sector with the transportation sector. Then, once photovoltaic costs come down to under a $1.00 a Watt, Zero Energy Homes will emerge that can use the solar power on the roof to not only power the house, but also the car. Conversely, the car could help provide a portion of the energy needs for the house when the solar resource is unavailable. Just like the Plug in Electric Hybrid Car reduces the amount of electric storage an electric vehicle needs, the integrated solar car/house would enjoy a similar benefit. Such homes could be built miles from power lines. Those that were built on our system would be welcome due to their capacitive features.

The Electric Utility of the Future will be a very different creature than the one of today.

It will be the unifying agency and central supplier of energy for all the energy sectors.

It will deploy and employ all kinds of distributed energy devices and strategies that will allow it to provide the maximum benefits to its customers.

It will move towards a non-carbon emitting future that integrates buildings, vehicles, and distributed energy generation into an operating whole.

And the air will be clean. And oil will become a relatively short, but historically significant transient chapter of human history.

originally published in EV World


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