Tesla posted an appetizer of sorts for its event tomorrow, via a blog post that details Powerpack 2, the second iteration of Tesla’s commercial and utility energy storage solution. The Powerpack 2 actually started shipping quietly in September, with a brand new energy module on board that’s capable of achieving twice the energy density or around 200 kWh of storage.

Powerpack 2 also has a new inverter designed and built by Tesla, and this is, according to the company, the “highest efficiency and highest power density utility-scale inverter on the market,” and also has the benefit of being easier to install.

Tesla says it has delivered batteries adding up to over 300 MWh in total energy storage capacity, which is an impressive feat given that in the U.S., an average home consumes around 11 MWh per year.

Tesla revealing this little piece of news ahead of time indicates that it wants to make sure there’s plenty of time and attention left for the remainder of its announcements tomorrow, which will include the first look ever at its integrated solar roofing solution, and Powerwall 2.0, its second-generation home energy storage solution.

We’ll be there and bringing you the news live on October 28 starting afternoon Pacific time.