Tools
For engineers and facility managers
Size the fix and see what it saves: notified maximum demand, power-factor correction, load factor and time-of-use, solar yield, battery peak shaving and variable-speed drives. Inputs are the numbers on an electricity bill or a nameplate.
From 12 months of maximum demand, recommend an NMD with headroom, estimate the capacity-charge saving and flag the risk of exceedance charges.
Size a capacitor bank from kW and power factor, and see the kVA reduction, demand-charge saving and payback.
From kWh by time-of-use period and the maximum demand, find the load factor, peak share, all-in cost per kWh and the value of shifting load out of peak.
Estimate generation for a South African city from typical specific yields, then split it into self-consumed and exported energy and value both.
Size the inverter kW and battery kWh needed to hold demand below a target, with cycles, expected life and a rough value of the demand saving.
Apply the affinity laws to a pump or fan duty profile and compare a variable-speed drive with throttling or bypass control: kWh, rand and payback.
For finance, commercial and investment people
Turn an energy project into the numbers a credit committee, CFO or investor asks for: a business case for several measures together, project and equity returns, levelised cost, own versus PPA versus lease, debt capacity, and what a kWh saved is worth.
Add results from the technical tools as measures, then see the combined capex, saving, payback, NPV and IRR, the cost per kWh saved and a cost curve. Save the project as a file.
A 1 MWp rooftop plant financed with senior debt: generation, PPA revenue, tax losses and the cash-flow waterfall, with returns, DSCR, LCOE and sensitivity.
The after-tax business case for an efficiency investment, with and without the section 12L allowance: NPV, IRR, payback and sensitivity.
The constant price per kWh that recovers capex and O&M over the life, in real and nominal terms, with a capex/O&M split.
Compare buying a rooftop plant, paying per kWh under a PPA, and a rent-to-own lease on the present value of cost, with an optional section 12B tax view.
How much senior debt a cash flow supports at a target DSCR, with a sculpted repayment and with a level annuity, capped by maximum gearing.
Escalate the tariff, discount the savings and see what saving one kWh a year is worth today: the most you can spend for a saving to break even.