Energy Storage & Grid Systems Workbench

Interactive workspace initializes in your browser. Engineering method, assumptions, validation, and references are available below.

Engineering reference

Energy Storage & Grid: theory, method, and sources

This environmental & energy engineering workspace publishes 11 governing equations, 5 stated assumptions, 1 documented boundary, and 2 sources so the numbers it returns can be checked rather than taken on trust.

Calculations run locallyCalculation & source methodology

How this tool works

Thirteen modules cover battery sizing and runtime, round-trip efficiency, cycle degradation, pumped hydro, thermal and flywheel storage, load factor, peak shaving, line losses, and a microgrid energy balance.

The microgrid module steps generation and demand against a state of charge with separate charge and discharge efficiencies, so curtailment and unmet load are reported rather than assumed away.

Calculators and topics covered

battery
storage
grid
microgrid
battery runtime
round trip efficiency
pumped hydro
peak shaving
load factor

Core equations

\text{battery energy:}\quad E = \frac{V \cdot \mathrm{Ah}}{1000}

\text{usable energy:}\quad E_{\mathrm{usable}} = E_{\mathrm{nominal}} \cdot \mathrm{DoD} \cdot \eta

\text{runtime:}\quad t = \frac{E_{\mathrm{usable}}}{P_{\mathrm{load}}}

\text{charge time:}\quad t = \frac{E}{P \cdot \eta }

\text{round-trip efficiency:}\quad \eta _{RT} = \eta _{\mathrm{charge}} \cdot \eta _{\mathrm{discharge}}

\text{cycle degradation:}\quad E_{n} = E_{0} \left(1 \frac{- \text{loss} \cdot n}{1000}\right)

\text{pumped hydro:}\quad E = \rho gVH \cdot \eta

\text{thermal storage:}\quad E = m \cdot c_{p} \cdot \Delta T \cdot \eta

\text{flywheel:}\quad E = \frac{1}{2} I\omega ^{2},\; \omega = \frac{2 \pi N}{60}

\text{load factor:}\quad LF = \frac{P_{\mathrm{avg}}}{P_{\mathrm{peak}}}

\text{line loss:}\quad E_{\mathrm{loss}} = I^{2} R \cdot h

Method and assumptions

Assumptions

Efficiencies are constant and independent of state of charge, temperature, and C-rate.
Cycle degradation is linear with cycle count; calendar ageing and depth-of-discharge sensitivity are not modelled.
Battery voltage is treated as nominal and flat across the discharge curve.
The microgrid balance uses fixed time-step energy accounting without dispatch optimization or reserve requirements.
Storage self-discharge, auxiliary loads, and power conversion limits are not included unless entered as an efficiency.

Limitations and design boundaries

Educational screening calculations only. Storage and grid design require certified equipment data, power and protection studies, chronological dispatch, thermal and fire safety, codes, interconnection rules, and qualified engineering review.

Sources and references

Primary sources are preferred for ratings, standards, manufacturer data, and externally defined constants.

Source policy

Linden and Reddy, Handbook of Batteries
Masters, Renewable and Efficient Electric Power Systems