Choosing between a heat pump and a biomass boiler for a greenhouse

We grow herbs year-round and heating is now our largest cost after labour. The current gas boiler is near the end of its life, so we are comparing an industrial heat pump with a biomass boiler fed by wood chips from a local sawmill.

The heat pump looks cleaner and simpler to operate, but our electricity tariff is volatile. Biomass fuel is cheap nearby, yet storage and ash handling require more work. Has anyone run either system in a commercial greenhouse, and how did real operating costs compare with the supplier estimates?