Love Love Love online calculators

A number of years ago I was working on refinancing our mortgage and went hunting for mortgage calculators online to help me wrap my head around comparing offers. For me it was like having a fraction of a machine out on the bench so I could tug at parts and trace the wires and look back at the manual and really internalize how the bits interact.  A great exercise.

In that spirit if you are trying to understand Levelized Cost of Energy you could do worse than monkey with the calculator here:

Simple Levelised Cost of Energy Calculator at NREL.gov

Even the disclaimer at the top is informative:

Note that this does not include financing issues, discount issues, future replacement, or degradation costs. Each of these would need to be included for a thorough analysis.

(I might add salvage cost but that is a pretty good list.)

Let's take a look at some of the figures it integrates:

Capacity Factor: There is a link to a map and a less than graceful explanation of the CF. It is entered as a positive number. The pop up description says it is a fraction expressed in a decimal but you enter it in the calculator as a percentage. Anyhow, the idea is no system runs all the time at 100% so you need to factor that in. In the case of Solar that pesky sunset to sunrise period really packs a wallop on the Capacity Factor. Clouds too.

Today's Utility Rates: This does not take into account the tiered structure of most utility rates. Which is understandable as that alone would take ridiculous amounts of programing just to capture the inputs, let alone analysis. There are programs that do it but for simplification an average price of electricity will do.

Go monkey with that calculator and see what you think. If you know of another, add it in the comments.

What that calculator does not provide is insight into the Time Of Use values and Demand Charges which can play a serious role in the cost structure for large utility consumers. Modeling those is a much more case-specific task and requires extensive energy audits to generate the data to feed the evaluation.