Engineering Calculators
A free toolbox of power distribution and solar engineering calculators. Enter your values and get a sized component, a reference price and a worked calculation in seconds — each tool links to the matching QDTB product line.
⚡ Power System Configurator — Build & Price Online
Design a complete power system in 4 steps: power sources, distribution, transformer and protections. Instant BOM, drawings and price.
System-level design calculators
42 free power engineering calculators
Complete LV/MV distribution design: transformer sizing, HV/LV switchgear, cables, grounding and protection — IEC/NEC/GB compliant, with BOM and FOB pricing.
Utility and C&I solar sizing with map-based solar resource, P50/P75/P90 yield, string/inverter matching and full-cost LCOE.
Utility-scale PV plant + grid interconnection: voltage level, main transformer, collector system, reactive power and substation BOM.
Tier-ready data center power: UPS runtime, PDUs, redundancy (N+1/2N), cooling load and complete BOM with pricing.
Industrial park master power plan: demand load, transformer count, MV distribution and cost roll-up for the whole site.
Oilfield electrification: pumping units, ESP loads, injection pumps and off-grid genset sizing with protection coordination.
Refinery and petrochemical power: process loads, hazardous-area equipment, genset backup and harmonic-heavy busbar design.
Port cranes and metallurgy: heavy cyclic loads, dynamic braking, harmonic mitigation and crane-duty transformer sizing.
Mining camp and pit power: MV overhead lines, skid substations, drill/ventilation loads and rugged protection.
Urban infrastructure: road/area lighting, traffic, flood pumps and RMU-based LV/MV networks sized to code.
Hospitals, schools and public buildings: ATS, EPS, emergency diesel and code-mandated backup sizing.
Water pumping stations: pump groups, soft-start/VFD, well/spare pumps and energy cost over the project life.
Wind + solar + storage hybrid: resource blending, storage sizing and LCOE vs diesel displacement analysis.
PV + storage + EV charging stations: DC fast-charger load, battery cycling and integrated BOM with pricing.
How to use these calculators
- 1. Pick a tool below. Each calculator is a self-contained page with its own inputs, formulas and worked example.
- 2. Enter your load, voltage, material or site values. Defaults are sensible — change only what you need.
- 3. Read the result: a recommended size or model, the step-by-step calculation, and a reference FOB price where pricing applies.
- 4. Copy the result link to share a specific configuration, or embed the tool on your own site.
Explore solutions by industry
Each industry solution links to a dedicated design calculator.