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Why New Daedalus?

Daedalus was the mythical great architect and artificer of the classical world. Today, embedded intelligence is enabling the most profound changes in the way we create and use buildings since his day.

Building Intelligence meets the Intelligent Building. The Intelligent Building negotiates with the Intelligent Grid. How will this transform how we interact with the physical world?

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Electric Cars will not be useful for Demand-Response

If a performing electric car were to arrive today, with adequate batteries at reasonable cost, it could well push today’s non-transactive energy infrastructure over the edge. Usually I write about intelligent building agents; when I write about the power grid, it is to discuss transacted energy purchases between those agents and an intelligent transaction grid. Today, I am going for those transactions on that grid, but leaving out the building. But first, a little on the building with cars.

There a lot of hopeful scenarios in which peak shaving is enabled by commuter cars plugged into office buildings. Peak shaving, initiated by what are called Demand-Response (DR) signals from the grid, is when buildings lessen their electrical demands to avoid peak periods of energy use. The story goes that we will go to work, and plug in our cars. When the DR event arrives, the building will run off the combined car batteries, reducing demand on the grid.

DR is very important for today’s grid, because the power supplied at the peak is the most expensive and usually the dirtiest to generate. I have seen numbers suggesting that as much as 17% of the grid’s capacity is used for less than 120 hours per year. If we manage peak electrical use, we have effectively grown the power grid for free.

Cars and their batteries, however, will never be an effective peak shaving tool for office buildings. Leave aside for the moment all HR-related issues associated with employers paying for commuting costs, and look at the people. Peak load occurs in the afternoon, and extends into the early dinner hour.

If I live some distance from my employer, will I be willing to end each day with a low charge on my car? Only until the first day I run out on the way home, perhaps because of an unanticipated need to attend a school event for my children, or to attend to a medical issue for my parents, or even to pick up some supplies for a social event. In any case, the first time it happens, I will resolve to park away from the building thereafter.

If I live close to work, I will arrive with my car already charged up. DR participation, always in the afternoon, will leave me always wondering whether I am subsidizing the company. The first time I am turned down for a raise, this thought will begin festering into a general resentment of my employer. Sub-vocal mutterings with phrases such as “blood-sucking leeches” come to mind.

Whether I live far away or whether I live close in, sooner or later I will leave early to head off for a summer (most DR events are during warm weather) weekend at the beach and find that despite my plans, my employer and its building have drained my car.

No, we cannot turn to electric cars to solve the DR needs of our office buildings. Not if actual people are involved. Perhaps if we make sure that our grid is intelligent and two-way transactional we can see a way past this.

I will try to write soon on what intelligence is needed, in grid and car, for more realistic use of more than a few electric cars.

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Reader Comments (2)

I've always liked this quote "“SmartGrid means you fill up your car with hydrogen but cannot drive it the next day, because your teenage daughter has sold the hydrogen as electricity at peak tariff over the internet, and used the proceeds to charge her mobile phone card.”- Hans De Keulenaer

June 25, 2008 | Unregistered CommenterMichaela Barnes

And undoubtedly, you will not be allowed to know what she sold it for under privacy laws....

June 25, 2008 | Registered CommenterToby Considine

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