Until we can manufacture solar panels on Mars, maybe the best option is solar power satellites with microwave transmission.

One of the big drawbacks on Earth is that you have to launch the satellite to orbit. For Mars, stuff is in orbit when it gets there, and landing it is the challenge.

Mars has an axial tilt similar to Earth's, which means that, like Earth, a satellite in stationary orbit will have full "noon" sun 99.5% of the time. A solar panel in stationary orbit around Earth will collect five times as much energy in 24 hours as one on the ground. The Martian atmosphere would filter less sunlight, so call it 4X for Mars.

Batteries are getting cheaper on Earth but they're still a lot of mass to send to Mars. Near-constant uptime with satellites mostly eliminates that problem.

At first, you do have to land the ground collector, but it's mostly antenna wire. Should be pretty robust and you won't have to worry about keeping the dust off it. Once you're making metals from Martian dirt, you can produce most of it locally, from dirt.

The biggest downside compared to nuclear would be that dust storms would at least partially block transmission.