To the editor:

What is an electrical grid and how does it work? An electrical grid can be likened to a water reservoir fed by rivers and streams. The water pressure is maintained by the depth and constant flow of water into the reservoir. As water is needed by cities and farms, water is released. Users cannot pick only water from clean mountain streams and not from the river that runs through an industrial area.

However, an electrical grid cannot store up electrical power like a reservoir. The second a kilowatt of energy is generated, it enters the grid and becomes like water in a pipe. It flows to where it is needed.

Giant batteries to store power are not yet available. Therefore, the manager of the grid, Puget Sound Energy in our case, must constantly balance the load by bringing online (or taking offline) additional generators to fill the gap provided by base load suppliers; hydro, wind and coal.

Balancing the load is both an art and a science helped by constant monitoring of voltages (the pressure).

If PSE puts too many kilowatts in the line, it can overheat and burn out a line; if too few, brownouts happen or the power fails.

Were Bainbridge to contract with Bonneville, it would sell us hydro to feed the PSE grid, and take it away from some other private user. That user would have to switch to coal or nuclear.

DAVE MACKENZIE

Bainbridge Island