Bringing the grid offering to real customers–what Sun calls the retail grid–was more problematic, and Sun has struggled to iron all the kinks out of the hardware, software, telecommunications, and other issues that are involved in building a utility.

While Sun doesn’t want to be a utility data center itself, it needs to operate at least some real utility centers as a means of doing product development and to help its customers–who will create and operate utilities–do a better job at it. And because Sun is not exactly operating at a profit these days, the Sun Grid was supposed to have retail customers who would, at $1 per CPU per hour, basically help foot the bill for the development of grid utilities.

That has been the theory for nearly a year, and now it is finally starting to become the practice. Virtual Compute Corp, a Houston company that was established to create and sell portable high-performance computing clusters and related storage to oil and gas companies in the US and the UK, has acquired 1 million CPU hours (presumably at a pretty respectable discount), to become Sun’s first retail Sun Grid customer.

VCC has 256 Xeon processors in Boston, 1,024 Opteron processors in New York, 3,000 Opterons in London, and 512 Opterons in Scotland prior to making the announcement that is would be reselling Sun Grid capacity. VCC is buying time slices on Sun’s V20z Opteron servers, which are one generation back from the current Galaxy Sun Fire machines.

VCC’s current machines have a total of 4,792 CPUs, and there are 8,766 hours in a year, so it has already invested in 42 million compute hours per year in its own IT infrastructure. You can bet it spent somewhere around $20 million acquire those servers (call it an average selling price of $4,000). Which is why VCC is testing out the Sun Grid alternative to adding capacity for its customers. This way, VCC only spends money when it makes money.