I spoke today with Bob Mobach – one of my technology gurus at Logicalis – about my concerns about the non-green generator.  After much discussion and research, we have again validated our decision to move forward with the generator.  He had some excellent insights about why we are in this position, and when some of the alternative technologies are more appropriate.


NCTD requires a high-availability environment now.  There is no getting around the fact that we run important, mission-critical systems on our infrastructure, and as such we can no longer afford to have unexpected and unplanned outages.  To meet this basic requirement, we must have the capability of creating power on-demand, nearly instantaneously should our power fail.  There simply are few choices on the market today to address this need for a facility of our size.


We could have taken the approach that we would provide our own ‘co-lo’ power via a set of natural gas generators.  This scenario would have allowed us to failover to SDG&E power should the natural gas units fail.  This option does not really make sense for our data center because firstly we’ve invested in solar pv power to offset the power demands, and secondly because our data center power draw is really too small to make this economical.  So from a business case, this is a poor choice for our scenario.


Another option was the fuel-cell based UPS.  The problem with this approach is simply the cost and the durability of the power.  We have had now two outages this year over 6 hours in duration.  There is simply no way we could sustain the entire data center on the fuel cells for this long.  And again, the business case is not there.


We are now investigating alternative fuel sources for the Kohler generator – either ‘clean diesel’ or biofuels.  While the biodiesel seems like a natural choice, the biggest issue is the long-term storage of the fuel.  Fuel that sits around for months can degrade due to algae or condensation.  Research indicates that not many entities are yet using biodiesel as their fuel choice for standby scenarios where the generator is not going to be used frequently.  So my next step is to contact the manufacturer to determine whether a biodiesel mix is appropriate in the generator, and what they would believe the ideal mix to contain.  We will then compare this to the emissions, performance, and price of ‘clean diesel.’


So while I am still not 100% reconciled that installing a generator is moving us in the right direction for a green data center, I am convinced that we’ve made the business decision which balances our environmental needs with our business realities.