Size it, spec it, check your work
Free calculators, guides and practice tools for the electrical side of data center, solar and battery-storage projects. Every calculator shows its method; every practice board checks your work.
Three ways in
Most people arrive with one of three questions. Each of these opens onto the rest.
Work it out
Twenty calculators — voltage drop, transformer sizing, arc-flash incident energy, cable ampacity, fault current — each showing the method, not just the answer.
Understand it
Thirty-three guides, each written to answer a single question — how a nameplate reads, what an arc-flash boundary is, why PUE lies to you — plus a plain-language glossary.
Practice it
Open boards for laying out real equipment — a one-line, a packaged power module, a rack elevation — with the result checked against sizing, load and code rules as you build.
Get it wrong here, not on site
Three open boards for laying out real equipment and having the result checked against sizing, load and code rules — with 32 procedural 3D models of the actual kit behind them.
Three sectors of power equipment
Each opens onto the guides, reference specifications and standards for that sector.
Data centers
Transformers, switchgear, generators, UPS, CDUs and busway for hyperscale and colo builds.
Renewables
Modules, inverters, trackers, GSUs and balance of system for solar, wind and hybrid sites.
Battery storage
DC blocks, PCS, BMS, EMS, fire suppression and thermal management for utility-scale BESS.
Guides that answer one question each
No overviews, no listicles. Each one takes a single thing engineers actually get asked and works through it properly.
How to Read a Transformer Nameplate
kVA ratings, cooling class codes, impedance, BIL and vector group: what every field means, and which ones decide the rest of your design.
Transformers & substationThe Grid Interconnection Process, Explained
What happens between filing a request and energizing: queue position, the study sequence, cluster studies and the agreement — with ERCOT, MISO and PJM compared.
Grid interconnectionFEOC Compliance for Solar & Storage
What the FEOC rules mean for a project, what documentation to gather, and how they interact with the domestic content bonus.
ComplianceBESS Fire Safety: NFPA 855 & UL 9540A
What NFPA 855 requires for battery storage, and how UL 9540A test data sets separation distances and suppression.
Battery storageWhy Transformer Lead Times Stretch Past 3 Years
What is driving the power transformer shortage, and how to plan a project schedule around it.
Transformers & substationLiquid vs. Air Cooling for AI Racks
Why GPU rack density is pushing data centers to liquid: direct-to-chip, immersion and rear-door heat exchangers compared.
Data center power & coolingNot sure what you need yet?
The tools hub lists everything on the site in one place — every calculator, every practice board and the glossary quiz. Nothing needs an account.
Browse all free toolsWhere the numbers come from
Every figure on the site carries a basis, and the methodology page sets out how each is derived, what it is good for, and where it should not be relied on.
Read the methodology