Most electrical energy consumed in the US is generated by burning fossil fuels. That energy had to be generated, transported, and then used to charge your battery, which has losses at each step. It also has to move a lot more mass in a typical EV than in their ICE counterpart, and especially in this Hummer.

So no, it's not really that efficient in terms of energy use -- a train or a bicycle and even a fossil fuel burning bus would be a lot better. And even compared to a normal car, unless you are installing your own solar panels to charge it, it isn't guaranteed to be less efficient in terms of carbon emissions, and with the Hummer it's been widely spoken of that they are far worse than even the ICE Hummer.

The only point you might have is air pollution, but the power stations are still burning that fuel and they are often doing so in or near cities. Car tires also produce toxic dust from friction with the roads and since EVs are heavier than other cars on average, they tend to produce more of this dust.

There's a marginal improvement in all of the EV business to what we were doing before, but there are still so many better options, like the e-bike. And if your choice is the hummer than you really can't claim any