Hi,

I have a question relating to the 'Help' on the hydropower calculations in WEAP. I'm currently trying to estimate fixed head for use in run of river hydropower nodes from a historic record of energy output (in kWh) and a known flow sequence.

Looking at the Help files I'm told that Energy output in GJ is given by:

Energy (GJ) = Volume * hydro-generation factor

Where the Hydro-generation factor is given by:

1000 * Drop elevation * Plant factor * efficiency * 9.806

Rearranging for drop elevation and assuming plant factor of 100% and efficiency of 70% gives

Drop elevation = Energy / (Volume * 1000 * 1 * 0.7 * 9.806).

Now my energy data is given in kWh which means I also need to divide my final result by ~277.778.

Doing this final step to match the Giga-joules quoted in the Help changes my results from potentially accurate, ~5m to 30m, to values of cm or less which seems extremely unlikely.

It would be useful if someone could highlight my mistake or clarify if this is a mistake in the Help and the value of energy should be given as kWh.

Thanks,
Jack