About
An energy engineer who builds the financial model too.
I'm an energy engineer with eight years of industrial experience and a Certified Energy Manager. I work where plant physics meets project finance: modelling solar PV, battery storage, wheeling and efficiency projects in the detail that lenders and investment committees need, and stress-testing the deals around them. This site shows that work: illustrative case studies, interactive calculators, and Excel models you can audit line by line.
01How I work
Five habits behind every number on this site
- 01
Start from measured data
Bills, interval meter data and load profiles come before brochures and rules of thumb. Most of what a site can save, or how much solar it can absorb, is already in its half-hourly data.
- 02
One model, every number traceable
Formula-driven, FAST-style models with the inputs in one place, so every figure in a report traces back to an assumption you can see and change.
- 03
Stress it the way a lender will
Tariff, yield, capex, interest rate and tenor, one change at a time, before anyone else does. On a contracted project the downside case matters more than the base case.
- 04
Check it a second way
Headline numbers are rebuilt independently: a second implementation, a published benchmark, or NREL's System Advisor Model. A model that has only been checked against itself has not been checked.
- 05
Write it for both readers
A technical summary for the engineer and a financial one for the person approving the money, from the same numbers, in plain language.
See the habits applied, line by line.
02Experience
8 years of industrial experience
May 2024 – present
Group Energy Engineer
Idwala Industrial Holdings
Energy engineering and financial modelling for the group's renewable-energy and efficiency portfolio: reviewing developers' PPA term sheets and models, and building solar PV, battery storage and wheeling business cases.
Nov 2023 – Apr 2024
Energy Application Engineer
Veolia Services Southern Africa
Technical lead for the Southern African energy services division.
Jun 2021 – Oct 2023
Energy Solutions Engineer
Energy and Combustion Services
Energy audits, modelling and financial analysis for coal, gold and platinum mining clients, including DCF, LCOE and NPV models for decarbonisation investments.
Jul 2017 – Feb 2020
Mechanical Engineer
CMG Pumps
Mechanical engineering design, execution and maintenance.
03Credentials
Qualifications
- CEM
Certified Energy Manager
Association of Energy Engineers · 2023
- PGDipPM
Postgraduate Diploma in Project Management
MANCOSA · 2020
- Degree
BSc Mechanical Engineering
University of KwaZulu-Natal · 2017
Certified Energy Manager, Association of Energy Engineers (2023); Postgraduate Diploma in Project Management, MANCOSA (2020)
04Expertise
Four areas, one question: does the project pay?
Energy efficiency
Finding the savings, proving them, and turning them into a case a finance committee can approve.
- Energy audits and facility energy balances
- Significant energy users and load profiling
- Compressed air, conveyors, pumps, HVAC and lighting
- Business cases, M&V and the section 12L allowance
Energy cost and tariffs
Reading the bill line by line and matching the tariff to how a site actually uses power.
- Time-of-use, demand and NMD charges
- Bill validation and tariff selection
- Wheeling: landed cost and line losses
- Eskom and municipal tariff structures
Renewable energy and storage
Sizing solar PV and batteries against real load profiles, tariffs and grid constraints.
- Solar PV and battery project leadership
- Battery peak arbitrage (8,760-hour optimisation)
- Embedded generation and wheeled PPAs
- Yield, degradation and P50/P90
Project finance and investment analysis
Building the cash-flow model, stress-testing it, and structuring the deal so lenders and sponsors can both say yes.
- Formula-driven, FAST-style financial models
- Debt sculpting to DSCR covenants, IDC and DSRA
- Section 12B and assessed-loss timing
- Lender stress tests and PPA term-sheet review
05Contact
Have a project that needs both the engineering and the model?
Energy-efficiency cases, tariff questions, solar and storage, or a model that needs checking before it goes to committee. Email is best.
- linkedin.com/in/thabisokali
Based in Johannesburg, South Africa.