How much heat a hot gas or flue gas can give back — as steam or to heat another stream — with fuel saved, CO₂ avoided and payback.
USD 49 one-time purchase
Buying several tools? Get the Heat Exchanger Complete Kit — USD 179
Need it once? Use it online: check your data free, unlock results from USD 9 for 3 runs.

What it does
Steam generation
Heat recovery steam generator with pinch and approach, blowdown, optional superheat and a stack temperature limit.
Or heat a stream
Heat a liquid or gas with minimum temperature differences at both ends; receiver flow calculated or given.
Any hot stream
Flue gas, process gas or liquid from the fluid library, or a gas mixture.
Money and emissions
Fuel saved, cost saved per year, CO₂ avoided and simple payback.
Zone duties
Economiser, evaporator and superheater duties and a temperature–heat diagram.
Print-ready report
Inputs, results, findings and the chart on A4.
Built for engineers
- Visible formulas — nothing hidden, so you can check every step.
- Fully referenced — methods from the standard references, checked against their published worked examples.
- Safe to share — sheets are protected against accidental edits, with an open password so you can still customise.
- Built-in input checks — clear warnings for impossible inputs and values outside typical ranges.
For engineering estimates; verify against site data. Code-based methods are aligned with the publicly documented procedure; they are not a licensed reproduction or a certification.
Preview the workbook
An illustration of the sheet layout of this workbook, not a screenshot of calculated results. Select the image to enlarge it. For questions before you buy, email [email protected].
Specification and checks
| Format | Excel workbook (.xlsx), no macros |
| Version | v1.0 |
| Works in | Excel 2010 or later, Windows and Mac |
| Units | SI, US and British, mixed freely |
| Includes | Guide tab with method and references, calculator, print-ready report |
| Checked against | Flue-gas steam generation and hot-water cases within 0.1 % of an independent reference calculation. See the verification record |
| Free version | Try the online calculator |
Online tool or Excel workbook?
| Online tool | Excel workbook (this page) | |
|---|---|---|
| What it does | The same sheet as the Excel workbook, run in your browser | How much heat a hot gas or flue gas can give back — as steam or to heat another stream — with fuel saved, CO₂ avoided and payback. |
| Cost | Check your inputs free. Results: 3 runs for USD 9, or every online tool for USD 15 a month (USD 99 a year) | USD 49 once, yours to keep |
| Input checks and findings | Every input checked; findings with the unlocked results | Every input checked, with findings and recommendations |
| Report for your calculation file | Printable results sheet | Print-ready report with your plant, tag, document number, revision and sign-off |
| Formulas | Method described in the guide | Every formula visible in its cell |
| Save, edit and rerun your cases | Each run separately | Yes: keep and edit your own file |
| Works offline, on a plant PC | No, needs the internet | Yes: Excel 2010 or later, Windows and Mac |
Online access and the Excel workbook are separate licences: one does not include the other.
Compatibility, licence and support
| File | Excel workbook (.xlsx), no macros, version v1.0; works in Excel 2010 or later on Windows and Mac. Sheets are protected against accidental edits, with an open password so you can customise. |
| Licence | Single user. A team licence (up to 5 named users) is 3 × the shop price; site licences on request — licence terms. |
| Updates | Updates to this major version are included; download them again from the link in your receipt. |
| Support | Email [email protected] with your order number — questions on the method, your inputs or your results are welcome. |
| Refunds | If the tool does not work as described, or has an error we cannot fix, email [email protected] with your order number within 14 days of purchase and we will refund you in full. Refunds are not offered for a change of mind once a file has been downloaded. Read the full refund policy. |