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FCC Requires Backup Power For 210K Cell Towers
1sockchuck alerts us to an article in Data Center Knowledge that explores ramifications from the FCC's decision a couple of months back to require backup power for cell sites and other parts of the telecom infrastructure. The new rule was prompted by wireless outages during Hurricane Katrina. There are more than 210,000 cell towers in the US, as well as 20,000 telecom central offices that will also need generators or batteries. Municipalities are bracing for disputes as carriers try to add generators or batteries to cell sites on rooftops or water towers. The rules will further boost demand in the market for generators, where there are already lengthy delivery backlogs for some models.
To provide solar power to a cell site would require several hundred square feet of space to mount the panels. Sizing a solar power system for infrastructure requires planning for when the amount of sun is at the minimum (approx 2 hours during wintertime at northern latitudes). A aolar system must put a full charge on the battery system to account for charging losses, battery inefficiency, and the continual demand of the load. To match up to a solar power system you need a very significant battery string (when I do system calculations I assume that the system can go for three days without sun). Mounting a wind turbine on a cell tower is problematic too. An antenna structure has a loading (ANSI 222 (f or g)) that has to account for ice, maximum wind and the surface area of the tower, feedline, antennas, etc... A wind turbine adds ALOT of loading to a structure. I suspect that 90% of the cell towers out there right now could not pass the structural analysis under ANSI.
Tisha Hayes
Regarding hurricane Katrina:
I work for a large cell carrier. We had backup power to every single cell in the area. In fact, after the hurricane we were doing pretty well, though some of the towers were taken out by debris. Only a couple were actually submerged. We lost a few trunk lines, but for the most part the system was working.
The problem was we didn't have any way to get gas to the generators. The roads were impassible, and based on news reports we were reluctant to send crews in to the sites we could reach for security reasons. So after a couple days the cell sites started going offline one at a time as the generators ran out of power.
As far as I know every one of our sites, in the entire country, already has a couple days worth of backup power.