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Smart grid, part 1: the need
Two smart grid articles recently appeared and disappeared in the holiday shuffle. Both are too good to let slip, and because I know almost no one actually clicks the links, I’ll use them as the basis for a few backgrounder posts on a technology that will be affecting all of us quite a bit over the next few decades.
First installment: why do we need a smart grid?
As this article from Tyler Hamilton makes clear, one reason is simply that our old electrical transmission system is physically antiquated and technically out-of-date:
> The transformer devices in a typical electrical substation — that is, a point on the grid where power is converted from a higher to lower voltage (or the reverse) — are designed to last 40 years. The average age of transformers in North America is currently 42…
> There are 275,000 substations in the world, 70,000 of them in North America. Most are filled with electromechanical control devices, the equivalent of analog in a digital age or the typewriter of the computer era.
Obsolescence has consequences:
> Compared to the phone or cable company, which can pinpoint and often fix network problems remotely, the local electric utility typically relies on phone complaints from customers to find out about outages on the distribution network. It then sends a crew to wander the streets in search of the failed equipment or line…
> The grid today has 99.97 per cent reliability, meaning you can expect about three hours of outage time a year. On the surface it sounds acceptable, but in the age of the Internet and Web commerce most data centres now require 99.9999 per cent reliability, amounting to about 30 seconds of downtime annually.
Beyond the physical degradation, the existing grid is fundamentally unsuited to accommodating the large amounts of renewable energy we need to address climate change. This fantastic overview from MIT’s Technology Review starts with an anecdote about Vattenfall Europe Transmission, the company that operates northeastern Germany’s electrical grid. Germany leads the world in wind power production, but this fluctuating and unpredictable energy source requires constant vigilance. A team of engineers works constantly on a reactive basis, firing up back-up natural gas plants as needed, or making spot electricity purchases from external suppliers.
The process is both expensive and environmentally wasteful. But at least Germany reaps the benefits of clean energy. In the U.S., our outdated grid prevents the wind farms from even getting built:
> The Midwest Independent Transmission System Operator, which manages the grid in a region covering portions of 15 states from Pennsylvania to Montana, has received hundreds of applications for grid connections from would-be energy developers whose proposed wind projects would collectively generate 67,000 megawatts of power. That’s more than 14 times as much wind power as the region produces now, and much more than it could consume on its own; it would represent about 6 percent of total U.S. electricity consumption. But the existing transmission system doesn’t have the capacity to get that much electricity to the parts of the country that need it. In many of the states in the region, there’s no particular urgency to move things along, since each has all the power it needs. So most of the applications for grid connections are simply waiting in line, some stymied by the lack of infrastructure and others by bureaucratic and regulatory delays.