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Glossary

Short definitions of the terms used throughout the Sympheny optimization model. Each term links to its concept page — read those for the full explanation and parameters.

Term Definition Read more
Hub A geographic area or site in your project — an individual building or a group of buildings treated as a single unit — for which you define demands, supply options, and connections. Hubs
Energy carrier Any substance or medium that contains energy and can be converted, stored, or delivered — a fuel, electricity, thermal energy, solar irradiance, and so on. Energy carriers
Energy demand An hourly profile (8,760 values, in kWh) of energy use that the system must satisfy at every time step. Energy demands
Stage A phase of investment and operation in a project's lifetime; technologies can be installed at a stage's start and reused or salvaged at its end. Stages
Import Energy purchased from outside the system, such as grid electricity or natural gas. Imports
Export Energy sold or sent outside the system. Exports
On-site resource A renewable resource with intermittent availability — such as solar irradiance or wind — described by an hourly profile. On-site resources
Conversion technology A system that transforms one or more energy carriers into different ones — for example, a gas boiler converting natural gas to heat. Conversion technologies
Storage technology A system that stores energy for later use. Storage technologies
Network technology A connection that moves energy between hubs. Network technologies
Technology package A bundle of technologies considered together in the optimization. Technology packages
Intra-hub network A connection that moves energy within a single hub. Intra-hub networks
Clustered profiles Machine-learning-generated representative days that stand in for the full year of hourly input data, reducing solving time while preserving hourly variation within each day. Clustered profiles
Discounted cash flow (DCF) analysis The method Sympheny uses to convert expected future cash flows into present value, accounting for the cost of capital, loan structures, and risk premiums. Discounted cash flow analysis
Capital recovery factor (CRF) The factor Sympheny uses to convert a present cost into an equivalent annual cost, making investments with different lifespans comparable. Capital recovery factor

For the full list of input and output parameters for each concept, see Parameters.