So it sounds like maybe 5kWh would be needed to melt snow/ice on a short run of stairs, but what continuous power level is needed? Maybe 300W of solar power ap

So it sounds like maybe 5kWh would be needed to melt snow/ice on a short run of stairs, but what continuous power level is needed? Maybe 300W of solar power applied over two days or 600W over one day would be enough to clear the stairs? Especially if you painted the stairs black. Maybe the stair heaters could be run sequentially from solar power to clear a stair at a time. A $1000 investment in 600W of solar panels and some black heating pads for the stairs seems like a reasonable cost (for some people or for a business worried about liability) for an often used small stairway to keep it clear for a few decades.