Neutron STEM Lab

Environmental & Energy Reference Center

Search detailed environmental and energy equations, parameters, design guidance, examples, units, and limitations.

Environmental & Energy Reference: labelled diagrams and key equations for reference, environment, energy, and equations.
Browser-local interactive workspace
Interactive workspace initializes in your browser. Engineering method, assumptions, validation, and references are available below.

Engineering reference

Environmental & Energy Reference: theory, method, and sources

This environmental & energy engineering workspace publishes 6 governing equations, 4 stated assumptions, 1 documented boundary, and 3 sources so the numbers it returns can be checked rather than taken on trust.

Calculations run locallyCalculation & source methodology

How this tool works

A browsable reference covering eleven areas: air quality, building energy, energy economics, energy storage, environmental systems, grid systems, lifecycle and sustainability, renewable energy, solid waste, water and wastewater, and general reference constants.

Each entry gives the governing relationship, typical value ranges, and the conditions under which the relationship applies, so a number found here can be checked against its stated basis before use.

Calculators and topics covered

  • reference
  • environment
  • energy
  • equations
  • environmental engineering reference
  • renewable energy reference
  • water treatment reference
  • building energy equations

Core equations

first-order decay:C=C0e−kt\text{first-order decay:}\quad C = C_{0} e^{- kt}hydraulic retention time:HRT=VQ\text{hydraulic retention time:}\quad \mathrm{HRT} = \frac{V}{Q}emission rate:E=C×Q\text{emission rate:}\quad E = C \times Qcapacity factor:CF=actual  energyrated  power×hours\text{capacity factor:}\quad CF = \frac{\text{actual}\; \text{energy}}{\text{rated}\; \text{power} \times \mathrm{hours}}levelized cost of energy:LCOE=CAPEX⋅CRF+O&Mannual  energy\text{levelized cost of energy:}\quad LCOE = \frac{CAPEX \cdot CRF + O \text{\&} M}{\text{annual}}\; \text{energy}conductive heat loss:Q=U⋅A⋅ΔT\text{conductive heat loss:}\quad Q = U \cdot A \cdot \Delta T

Method and assumptions

Assumptions

  • Values are representative published ranges, not site-specific measurements or regulatory limits.
  • Emission and energy factors vary by region, fuel, technology, and reporting year; the entries state a basis but local factors should be substituted.
  • Reference relationships assume steady-state, well-mixed conditions unless an entry says otherwise.
  • Nothing in the reference is a substitute for the governing permit, standard, or regulation in the relevant jurisdiction.

Limitations and design boundaries

  • Reference summaries are educational. Applicable laws, standards, emission factors, climate data, equipment ratings, and design criteria must be verified for the project location and date.

Sources and references

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

Source policy
  • Davis and Masten, Principles of Environmental Engineering and Science
  • ASHRAE Handbook—Fundamentals
  • ISO 14040 and ISO 14044

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