What is involved regulation wise adding an electric motor to a glider?

On Wednesday, February 3, 2021 at 11:35:51 AM UTC-8, Bob Kuykendall wrote:
On Tuesday, February 2, 2021 at 1:26:10 PM UTC-8, David Scott wrote:

Others have pointed out that this is easier for an Experimental glider. It is easiest for an experimental, amateur-built glider. For E-AB, depending on the operating limitations, you might have to notify the FAA and repeat Phase I testing. But nobody wants to see your engineering validation, and only the person signing off the annual condition inspection needs to review your workmanship. The FAA or DAR only wants to see that the paperwork is correct and that placards and operating limitations are correctly spelled out.. A good DAR will look the airplane over to make sure it doesn't look particularly dangerous, but they aren't required to.

We have FES going into one of our glider kits right now, and are preparing for the installation of electric self-launch systems in future models.

--Bob K.
Since I am new here what kit do you produce? Are you preparing for FES or retractable pylon?
Any idea how much thrust an FES produces? My search came up empty.