Built by an engineer.
Designed for engineers.
34+ years of electrical engineering experience in building electromechanical infrastructure — distilled into free, practical tools for the profession.
Why this site exists
“The same calculations came up again and again on every project. I built these tools for myself — then decided to share them with everyone.”
EfficiencyEval was created by a practicing electrical engineer with over 34 years of hands-on experience in building electromechanical infrastructure — from initial design and load analysis through to commissioning and performance evaluation.
Over the course of a long career, the same calculations came up again and again: How many batteries do we need for this UPS? What capacitor bank corrects this power factor? What is the carbon impact of this facility? These are not exotic problems — they are everyday engineering questions. Yet finding a reliable, straightforward tool to solve them quickly was always harder than it should have been.
EfficiencyEval was built to fix that. Every calculator on this site started as a tool the founder built and used in real projects. They have been refined, documented, and published here so that other engineers — and anyone learning the trade — can use them freely, without registration, without paywalls, and without unnecessary complexity.
Precision tools for real engineering decisions
Engineering decisions should be backed by accurate calculations, not rough estimates or expensive software licences. Our mission is to provide the engineering community with free, reliable, and clearly explained calculation tools that reflect real-world practice.
Built on real practice
Every formula reflects methods used on live building infrastructure projects, not textbook theory alone. If it’s here, it has been used on a real job.
Always free
No subscription, no login required, no hidden fees. These tools exist to be used by the engineering community — that’s the entire point of this platform.
Transparent methodology
Each calculator explains its inputs, assumptions, and the engineering basis behind the result. No black boxes — you always know what the tool is doing and why.
The experience behind the tools
With 34+ years as an electrical engineer specialising in building electromechanical infrastructure, the founder has worked across the full lifecycle of built environment projects — from feasibility and concept design through detailed engineering, procurement support, site supervision, and commissioning.
This depth of experience directly informs every calculator on this platform. The battery sizing tool reflects the same methodology applied in specifying UPS and standby power systems for real facilities. The power factor correction calculator mirrors the analysis carried out before recommending capacitor bank installations. The carbon footprint tool draws on the energy assessment work that now forms a standard part of building design and operations.
The tools here are not academic exercises — they are working instruments, shared openly with the profession.
More calculators coming soon
EfficiencyEval is an ongoing project. The current suite of three calculators will grow steadily to cover a broader range of engineering disciplines relevant to building infrastructure and energy systems.
Planned additions include tools for lighting design and lux level calculation, HVAC load estimation, cable sizing and voltage drop analysis, standby generator sizing, and energy audit reporting. A resource library covering engineering guides, worked examples, and reference data is also under development and will be published progressively.
Get in touch
Suggestions, errors, or methodology questions — every message is read and responded to personally.