EPOS-Plan models the energy supply of a building, a site or a district as one connected system: climate and demand on one side, generators, storage and hydraulics on the other, with economics behind them. All quantities are simulated over the 8,760 hours of a year, so that coincidence, storage behaviour and self-consumption are calculated rather than estimated.

This page gives a short overview of the building blocks of the program. The detailed description of each topic – model approach, key figures, sizing rules and practical notes – is on the linked subpages.

Boundary conditions

Site and demand come first. They determine every result that follows and should therefore be defined and checked before anything else.

• Climate data – Hourly temperature and irradiance data, altitude, design temperature and heating limit.
• Heat demand calculation – Space heating, hot water, process heat and network losses – from key figures or from metered consumption.
• Electricity demand and load profiles – Load profiles for residential, commercial and industrial sites, load peaks and additional consumers from the heat side.

Generators

EPOS-Plan combines any number of generators in a dispatch order and calculates their interaction hour by hour.

• Heat pump – Performance map, COP and seasonal performance factor, heat sources, bivalence and booster concepts.
• CHP – Combined heat and power, sizing by heat or power, operating modes and remuneration.
• Solar collectors – Collector types, efficiency model, orientation and integration into the store.
• Photovoltaics – Yield model, sub-arrays and orientation, self-consumption and self-sufficiency.
• Boilers and peak load – Condensing, biomass and electric boilers, district heating, sizing and cycling behaviour.

Storage

Storage decouples generation from demand. Its size and management determine self-consumption, running hours and the efficiency of the whole system.

• Buffer storage – Capacity, stratification, losses, switching thresholds and assignment to generators.
• Battery storage – Key figures, charging and discharging strategy, sizing and interaction with the heat side.

System and hydraulics

Only the hydraulic integration turns individual components into a working plant.

• Hydraulic schemes – Principle diagrams for heat pump, booster, storage and peak load with their advantages and disadvantages.
• Energy balance comparison – Balance boundaries, reference case, final energy, primary energy and emissions across variants.

Economics

The energy flows of the simulation translate directly into cash flows. Investment, operating cost and revenue are evaluated over the study period.

• Cost calculation – Investment, maintenance, fuel and electricity purchase cost, price escalation and subsidies.
• Revenue calculation – Electricity remuneration, avoided grid charges, heat revenue and the data basis from the simulation.
• Economic analysis – Net present value, annuity, heat generation cost, payback and sensitivities.

Related pages

How the building blocks work together inside the program is described under Program workflow. Real projects with figures are shown in the Examples, and the fastest way in is the Quick start guide.