I suspect some, or perhaps all, of the PowerPacks for these two projects may also be included in the 2016 purchase orders:
CMEEC turned to Tesla and SolarCity, the industry leaders in solar storage projects. Tesla and SolarCity partnered with Brightfields Development to develop 15 MW (AC) of solar PV across 5 sites, as well as a 1.5 MW/6.0 MWh energy storage system, the largest PV-paired storage system in the Northeast. https://www.tesla.com/sites/default/files/pdfs/en_US/Tesla_CMEEC-Case Study-2017.pdf
This does not look like a PO from SolarCity to Tesla:
"The 1.5 MW/6.0 MWh battery storage system will also be financed by Tesla and SolarCity and will be located at the Stott Avenue project site. The batteries are utilized to store solar energy produced during off-peak hours and later discharge this energy at times when CMEEC’s load is peaking, or coincident with the ISO-NE peak load. Tesla and SolarCity will implement and maintain a controls system that allows CMEEC to dispatch the battery’s energy in its preferred manner. By strategically discharging the battery in this manner, CMEEC will reduce the load they serve, and thus will pay lower capacity charges to ISO-NE for that peak event."