HKN Engineering

HKN / EPW + DDY

Methods and
verification protocols

Explore the method, file checks and an example using design days in EnergyPlus.

Read the protocols ↓

01 / EPW

Format and consistency

Checks accompany each result. Gaps, warnings and unsupported fields remain visible.

Per-file report

02 / EnergyPlus

Reference design days

The published example uses design days to size zone equipment and systems.

13 · EnergyPlus 26.1.0-6f2e40d102

03 / Observations

Local climate accuracy

A separate comparison with independent observations is required for the chosen location and intended use.

Not established

File and physical checks

After creating an EPW, the service checks its calendar, missing values, value ranges and physical relationships. Check results and parameters are available in the report and JSON. DDY is calculated separately from the multiyear NASA POWER series.

DDY requires at least twenty consecutive complete NASA POWER years. Checks cover the temperature, humidity, pressure and wind of the design days.

EnergyPlus sizing

To size equipment, select the required DDY design days in your EnergyPlus model. The day selection and sizing results depend on the model and software version.

The service prepares weather files. Equipment sizing is performed in your building model.

Independent climate validation

NASA POWER is a modelled weather source. Assessing local climate accuracy requires comparison with independent observations for the chosen location and intended use.

Download files and inspect provenance

An EPW + DDY result includes design days and their parameters: period, source data, method and checks. The download deadline is shown in your account.

Open your calculations to download results.

Hosting and queue

Calculations are processed in submission order. You can download a completed result while the next job runs. The exact download deadline appears in your account and email.

Verified example

The example lists the source files, EnergyPlus version and design-day check results.

Date
2026-10-22
EnergyPlus version
26.1.0-6f2e40d102
Period
2006–2025 · 13 design cases.
Warnings / severe errors
3 / 0

DDY · DDY provenance report · Verification receipt

Example checksums
Source manifest
655002937ea91e2975df039d949e2bd1e98beb189f5f44603459ce785c91e310
DDY SHA-256
a26dcfbd8e880d23b160c708476ffc2e0ca9e6190c9ec0d8e2acb12f3df44153
design_conditions.json SHA-256
bb97c2033e7ad9c041de036494cb868d744b3b73e294d1f424f296675083aa06

Open reference collection

Full protocols and files

Protocols are available without registration. Each document includes its date and checksum.