  We use a dynamic programming approach to construct management strategies for
a hydropower plant with a dam and a continuously adjustable unit. Along the
way, we estimate unknown variables via simple models using historical data and
forecasts. Our suggested scheme achieves on average 97.1 % of the theoretical
maximum using small computational effort. We also apply our scheme to a
Run-of-River hydropower plant and compare the strategies and results to the
much more involved PDE-based optimal switching method studied earlier by the
authors in (Optimization and Engineering (2021): 1-25); this comparison shows
that our simple approach may be preferable if the underlying data is
sufficiently rich.
