On March 20 more than 70 percent of the voters of Evanston approved community choice electricity aggregation. The measure authorized the City of Evanston to act as sole purchaser, or aggregator, of electricity on behalf of a pool, or aggregation, of Evanston residents and small businesses and other small organizations. The City will negotiate with vendors of electricity for a price lower than the present ComEd one.

Among the terms in the contract for purchase of this power will be the unit price, the term of the contract and the “mix” of sources of electricity. Nuclear-powered and coal-powered plants are two of the main non-renewable sources in Illinois. Sources of renewable energy include wind, hydro-electric, solar and bio-mass power.

Residents and small businesses that currently have ComEd as their supplier are eligible to be in the pool. Larger enterprises and those residents who already have a contract with an alternate retail energy supplier (ARES) are not eligible. Once the price is set, residents will have the opportunity to opt out of the pool and remain with ComEd as their supplier of energy.

Because there is a more open market for electricity than before, it is anticipated that residents in the pool will save up to 25 percent on the “supply” portion of their electricity bill, netting about a 10 percent overall saving.

The opt-out choice is individual, but another choice will be collective: the “mix” of power, that is, how much, if any, of the power will come from sources attributable to renewable energy in the form of renewable energy credits (RECs).

It would be easy to get lost in a green cloud and slide over discussion of the cost – or the savings – to the aggregate members. While there will likely to be a cost-saving on the supply side by virtue of shopping around for an alternative to ComEd, the higher the percentage of RECs is, the smaller that cost-saving will be – in dollars. The ecological saving will be greater with the higher percentage attributable to renewable sources.

There will of course be tension between the immediate cash savings and the longer-term environmental savings. Some residents may simply feel that they need as much reduction as possible on their electricity bill; others may be able to afford the longer view.

We urge residents to consider these options carefully. Those who are eligible to be in the pool and who opt out may still opt in at a later date, City officials say, but they may not necessarily receive the same savings as those in the initial pool.

The City will make the ultimate decision about the power mix; and City Council discussion on that issue is now scheduled for the April 30 City Council meeting. The discussion of the relative benefits of the lowest price versus the greenest mix is one worthy of a philosophy class. It looks like we have, for the next very few weeks, the opportunity to be in that classroom.