A bit of utility energy efficiency program managers insider baseball, so skip if not of interest!
I collected a bit of useful data yesterday at the Technology Convergence Conference hosted by Teladata in Santa Clara yesterday in a presentation by Eaton, a big provider of power delivery and conditioning equipment for data centers.
Eaton posted a short list of the expected useful life for four classes of equipment. That's obviously useful for data center facility managers who have to anticipate equipment replacements, and even for accountants who have to set depreciation schedules. (Well maybe not for the accountants as I suspect the schedules are set by IRS policy, not reality!)
Here's the list:
UPS equipment: 12 years
Transmission switchgear: 12 - 15 years
CRAC units: 10 years
Circuit breakers: 12 years
It's a pity we don't have estimates for power distribution units and distribution transformers, and I wonder if there isn't quite a lot of variation for cooling units (how long to CRAHs last?), but there's something here for utility program managers as well as data center operators.
For the DC managers, I wonder if they really plan for equipment replacement based on these time frames. In particular, I've seen switchgear and circuit breakers that have lived several lives based on these numbers!
For utility program managers, the UPS and CRAC units figures could be a good basis for establishing Effective Useful Life (EUL) metrics for your energy efficiency programs.
Let me explain that in layman's terms for non-program folks: If you approach a utility for an energy efficiency rebate for a UPS system that is say nine years old, they are likely to base the payment on the energy savings of a premium efficiency unit you might purchase, compared to a "standard" efficiency unit on the market today - not the difference between the unit you buy and the existing unit.
The premise is that at nine years old, you have to buy a new unit anyway, so the efficiency gain of buying a modern unit is a given. The utility will only reward you for going to a premium efficiency unit.
Now, if you replace a unit that is not close to the end of its EUL, the utility can provide more of an incentive because you are retiring the equipment early.
I'll look for more references to EULs for data center equipment out in the industry and pass them along as I uncover them.