Google today said it has joined the Open Compute Project (OCP), and the company will donate a specification for a rack that it designed for its own data centers.

Facebook founded the Open Compute Project in 2011 to share designs of servers and other data center equipment. Many companies, including Microsoft, have joined the project and contributed their hardware designs. While Google has been building its own hardware for years, it hasn't joined the project until now.

Google's first contribution will be "a new rack specification that includes 48V power distribution and a new form factor to allow OCP racks to fit into our data centers," the company said. Google will also be participating in this week's Open Compute Summit.

"In 2009, we started evaluating alternatives to our 12V power designs that could drive better system efficiency and performance as our fleet demanded more power to support new high-performance computing products, such as high-power CPUs and GPUs," Google wrote. "We kicked off the development of 48V rack power distribution in 2010, as we found it was at least 30 percent more energy-efficient and more cost-effective in supporting these higher-performance systems."

Machine learning is one area that's requiring higher-power workloads, Google noted. Google has been using its 48V infrastructure "at scale for several years," and the company said it's now comfortable enough with the design and reliability to share it with the world. The company said it hopes to help others "adopt this next generation power architecture, and realize the same power efficiency and cost benefits as Google."

Google hasn't submitted a proposed specification to the OCP yet, but the company is working with Facebook to get that done.

The rack design probably won't be the last contribution Google makes to the Open Compute Project. Though Google didn't say anything about revealing its server designs, it said it wants to work with the OCP on "disk solutions for cloud based applications" and new software for server and network management.