I try to make a point of keeping promises, even though I may not always keep them right away. So, in response to a gentle e-mail earlier today from a kind reader, this is the first of a couple columns about using direct current (DC) as an energy option in the data center. (As opposed to Alternating Current, or AC.)
I'm writing about this issue for two reasons: First, because there seems to be some new innovation surrounding this technology and, two, it's pretty clear that The Green Grid is starting to debate its own position on the topic as I mentioned in an earlier post. I don't really know what that position is, because I wasn't able to attend the organization's Technical Forum this week in San Francisco. However, it's something I hope to follow up on within the next couple of weeks. Meanwhile, for some light reading (ha!), here is an article about some of the Green Grid's earlier thoughts on AC vs. DC.
For the record, let me state that I don't have an opinion about the AC vs. DC issue yet, mainly because I am not an electrical engineer and I don't feel I'm adequately briefed to form one. I do know that DC is typically more often associated with batteries than anything else and that its historical challenge has been voltage degradation at distance. I am just writing about the options being presented to me in my capacity as a blogger on Green IT. To me, the whole thing is kind of like a VHS vs. BetaMax debate or substitute-your-favorite-format here argument, although the electric grid is a heck of a lot more ubiquitous and stands to have a bigger impact on our lives.
In any event, this first DC-related post is about a company called Validus DC Systems, which is in the process of introducing a new end-to-end integrated power infrastructure for data centers and for telecommunications companies. (More on telcos in my next post, when I report on my conversation with Eltek Valere, which creates power systems for telcos and industrial companies.)
Validus claims that its DC infrastructure technologies can help customers accommodate higher density data centers by distributing electricity throughout the data center more efficiently than AC designs. The company's founder and CEO Rudy Kraus pitches the "Hybrid Power" design of its products, saying that they combine the best of the AC and DC worlds. Here's a little backgrounder that outlines each of its modules. The bottom line: Validus believes that its technology can save up to 50 percent of the raised floor space in today's typical data center and reduce the energy consumption.
By way of further making the DC case, Kraus notes that the internal guts of pretty much anything electronic these days -- including computers, lighting and so on -- run on direct current already. What Validus has done is make DC more scalable, he says. "If everything downstream is DC, why would we want to send AC?"
That's actually a pretty good question, but one I'm not qualified to answer. How about you?
Finally, this is probably a sponsored report, but I'm going to share the link anyway, because it provides a good background on the AC/DC debate.
Next up: Highlights of my conversation with Eltek Valere.