Heat-duty and steam balance worksheet
Define the service boundary, then check every constraint. Built-in values are resettable fictional teaching examples; results prepare further review.
Efficiencies must be greater than 0 and at most 100%. Heads, usable volume, requested hydro power and duty duration must be positive. Machine/interface powers may be zero; a zero recharge window explicitly fails recharge.
Formulas, assumptions and limits
Single-phase path: signed stream MW = mass flow (kg/s) × c_p (kJ/kg·K) × (T_out − T_in) / 1,000. This assumes constant specific heat and no phase change.
Enthalpy path: signed stream MW = mass flow × (h_out − h_in) / 1,000. One metric tonne/hour = 1/3.6 kg/s. Enthalpy values must share one property reference and actual pressure/temperature/quality states.
Positive means the specified stream gains heat; negative means it loses heat. The useful magnitude is |stream MW| × the declared transfer fraction; energy = useful magnitude × hours. Heat removal does not by itself prove recovery into another process.
The target check compares quantity only. It does not verify temperature approach, pressure, steam quality, timing, heat-exchanger design or useful-service suitability. A declared evidence reference remains user-supplied, not independently verified.
No steam tables are generated. In steam mode enter independently verified inlet/outlet enthalpy; do not use c_pΔT across phase change. Use 100% transfer when the states already bound the useful service.
Prepare evidence for review
Bring dated mass-flow measurements, pressure/temperature and steam quality, verified property references, actual inlet/outlet states, simultaneous operating times and the receiving-process temperature requirements.
DOE · Industrial Heat Pumps for Steam and Fuel Savings
Reviewed 26 October 2026. Equations and examples are original teaching calculations; sources provide technical background, not equipment performance or project approval.
Sources and review date
Reviewed 26 October 2026. Text, diagrams and exercises are original. All numerical cases use stated teaching assumptions, rather than site measurements or manufacturer commitments. These primary sources support the technical background; verify their applicability to each project.
[H1] ARENA / HILT CRC · TES for Industrial Process Heat: A Practical Guide (2026) ↗
Integrated assessment of process heat and thermal storage.
[H2] IEA · How a Heat Pump Works ↗
Heat-source, useful-output and COP concepts.
[H3] IEA · Heat Pump Monitor 2026: Key Findings ↗
Industrial integration, temperature and economic context.
[H4] DOE · Industrial Heat Pumps for Steam and Fuel Savings ↗
Foundational engineering explanation; not a current local approval rule.