Googling a rough average returned 0.346 kwh/mile for electric cars between 2000 and 2022 (wide range, im aware). Traveling at 50MPH, you go 50 miles in 1 hour (assume you’re already going 50, and stay at that speed). So you’d use [0.346KWh/mile] *[50 miles/hour] = [17.3 KW] per hour @ 50 MPH
I just run a wireguard container on my raspberry pi 3b and use that to VPN onto my local network. Was super simple to set up