They're already incentivized to do this because the price varies with demand. Providers that can vary their output (at least some natural gas and coal sources) already do this on a daily basis, which you can see here: https://www.ercot.com/gridmktinfo/dashboards/fuelmix

The overnight low price is typically $20-$30/MWh. Yesterday during the shortage the price peaked at $5000/MWh, which I suspect might be an upper limit.