Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For Engineers · District Heating

District Heating for a flywheel store

Built for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed. Simulate a flywheel store live below — adjust the inputs and watch it respond, right in your browser.

Thermal Resistance

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Composite Wall Heat TransferLive

R-value & U-value

Controls

Presets

Drywall (mm)

Insulation (mm)

Brick (mm)

Inside temp (°C)

Outside temp (°C)

Heat flows through a wall like current through resistors in series. Each layer's thermal resistance is its thickness over its conductivity; adding them gives the total R-value, and the heat flux is the temperature difference divided by it. Insulation, with very low conductivity, dominates the R-value — the steep temperature drop shows where it does its work.

▶ Run in Python

Data Inspector

Total R-value2.71 m²K/W

U-value0.37 W/m²K

Heat flux9.6 W/m²

Governing equation

R = \sum \frac{L _{i}}{k _{i} A} = 2.71 \frac{m ^{2} K}{W}, Q = \frac{Δ T}{R} = 9.6 \frac{W}{m ^{2}}

Reading this result: The insulation layer carries the most thermal resistance, so the temperature falls most steeply across it. A total R-value of 2.71 m²K/W lets 9.6 W/m² flow for this 26°C difference.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

↓

LCOE

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Levelized Cost of EnergyLive

the true price per MWh

Controls

Presets

Capital cost ($/kW)

Capacity factor (%)

Discount rate (%)

Lifetime (years)

Fixed O&M ($/kW/yr)

LCOE spreads a power project's lifetime cost over every megawatt-hour it produces, letting wildly different technologies be compared fairly. It rewards high capacity factors and cheap capital, and punishes idle plants. The capital-recovery factor discounts future costs to today. It is the number that has made solar and wind the cheapest new power in most of the world.

▶ Run in Python

Data Inspector

LCOE$52/MWh

Per kWh5.2¢

Capacity factor25%

Governing equation

LCOE = \frac{C \cdot CRF + O}{C F \cdot 8760} \times 1000 = \frac{1200 \cdot 0.078 + 20}{2190} \times 1000 = 52 $/ MWh

Reading this result: At a 25% capacity factor the plant sits idle most of the time, so its capital is spread over few MWh — that thin denominator is what pushes LCOE up to $52/MWh.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

Is this good for engineers?: Yes — this version of "District Heating for a flywheel store" is framed for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.