Home / Glossary

Solar & Energy Glossary

215 plain-English definitions covering solar, batteries, inverters, wiring, generators, tariffs and the economics of going solar — from kWh and MPPT to NEM 3.0, LiFePO₄ and LCOE. Search, or jump to a topic. Policy terms are dated references; see our data changelog.

Electrical Basics Panel Tech Inverters Batteries Generators Wiring & Safety Tariffs & Incentives Appliances RV & Off-Grid Economics

Fundamental Electrical & Solar Math

Watt (W)

Base unit of real-time electrical power (W = V × A).

Kilowatt (kW)

1,000 watts; standard metric for solar array sizing and generator rated output.

Kilowatt-Hour (kWh)

Measure of energy consumption over time (1,000 watts used for 1 hour).

Megawatt-Hour (MWh)

1,000 kWh; unit used in commercial solar, utility billing, and STC calculations.

Ampere (Amp / A)

Unit of electrical current flowing through a circuit.

Volt (V)

Unit of electrical potential or pressure driving current through conductors.

Direct Current (DC)

Electrical current flowing in one direction, produced by solar panels and batteries.

Alternating Current (AC)

Electrical current that reverses direction, used by standard home appliances and the grid.

Power Factor (PF)

Ratio of real power (kW) to apparent power (kVA) in AC circuits.

Apparent Power (kVA)

Product of volts and amps (kVA = V × A / 1000), critical for sizing generators and transformers.

Peak Sun Hours (PSH)

Equivalent hours per day when solar irradiance averages 1,000 Watts per square meter (W/m²). Solar output calculator ›

Irradiance

Rate at which solar energy hits a surface area, measured in W/m². Solar output calculator ›

Insolation

Total solar energy received on a specific surface area over a given timeframe (kWh/m²/day). Solar output calculator ›

System Efficiency / Performance Ratio (PR)

Ratio of actual energy output to theoretical maximum energy output. System size calculator ›

Ohm's Law

Fundamental relationship defining voltage, current, and resistance (V = I × R).

Energy Consumption / Daily Usage

Total watt-hours consumed by a household or building over 24 hours.

Standard Test Conditions (STC)

Industry laboratory testing standard for solar panels: 1000 W/m², 25°C cell temp, 1.5 AM. String sizing calculator ›

Nominal Module Operating Temperature (NMOT)

Realistic field condition test standard for solar panels (800 W/m², 20°C air temp).

Temperature Coefficient of Pmax

Percentage drop in solar panel power output for every 1°C rise above 25°C. String sizing calculator ›

Nameplate Capacity

Maximum rated power output stamped on an electrical device or solar panel by the manufacturer. Solar output calculator ›

Joule (J)

The SI unit of energy: one watt sustained for one second. Too small for solar work day to day — 3.6 million joules make one kilowatt-hour — but it anchors every other energy unit.

Megajoule (MJ)

One million joules; 3.6 MJ = 1 kWh exactly. Appears on gas bills (especially in Australia) and appliance labels — converting to kWh lets you compare gas heating against solar-powered electric alternatives. kWh ↔ MJ converter ›

Horsepower (hp)

Legacy unit of mechanical power: 1 hp = 746 W of shaft output. A motor's electrical draw is higher after efficiency and power factor — a 1 hp pump typically pulls 0.9–1.1 kW, more at start-up. hp ↔ kW converter ›

Kilowatt-peak (kWp)

The DC nameplate rating of a solar array under standard test conditions (1,000 W/m², 25 °C). Real AC output at any moment is typically 75–85% of kWp after temperature, soiling, wiring and inverter losses. "A 5 kW system" almost always means 5 kWp of panels.

↑ Back to top

Solar Panel Technology & Mechanics

Monocrystalline Panel

High-efficiency solar panel made from single-crystal silicon. Panel comparison calculator ›

Polycrystalline Panel

Budget solar panel made from melted silicon fragments with slightly lower efficiency. Panel comparison calculator ›

TOPCon (Tunnel Oxide Passivated Contact)

Advanced N-type solar cell tech delivering higher efficiency and lower thermal loss. Panel comparison calculator ›

PERC (Passivated Emitter and Rear Cell)

Silicon cell technology with a reflective rear layer that boosts light absorption. Panel comparison calculator ›

Bifacial Solar Panel

Solar panel that absorbs light and generates power from both front and back surfaces. Panel comparison calculator ›

N-Type Silicon

Solar silicon doped with phosphorus, resistant to Light-Induced Degradation (LID). Panel comparison calculator ›

P-Type Silicon

Traditional solar silicon doped with boron, prone to initial LID performance drop. Panel comparison calculator ›

Open Circuit Voltage (V_oc)

Maximum voltage a solar panel produces when connected to no load. String sizing calculator ›

Short Circuit Current (I_sc)

Maximum current output from a solar panel when its terminals are shorted together. String sizing calculator ›

Maximum Power Voltage (V_mp)

Voltage produced when the solar panel operates at its highest efficiency point. String sizing calculator ›

Maximum Power Current (I_mp)

Current produced when the solar panel operates at its peak output point. String sizing calculator ›

Half-Cut Cell

Solar cell sliced in half to reduce internal resistance, lowering hot-spot risks and shade loss. String sizing calculator ›

Busbar (BB)

Conductive thin wires printed on solar cells that collect and transport generated electrons. String sizing calculator ›

Shading Loss

Drop in energy yield caused by shadows falling on part or all of a solar array.

Bypass Diode

Protective diode inside solar panel junction boxes that redirects current around shaded cells.

Tilt Angle

Angle of inclination between a solar panel and the horizontal ground. Tilt angle calculator ›

Azimuth Angle

Compass orientation of solar panels (e.g., 180° South in Northern Hemisphere). Tilt angle calculator ›

Solar Array

Entire connected system of multiple solar panels operating together. System size calculator ›

Ground Mount

Racking framework securing solar panels directly to the ground instead of a roof. System size calculator ›

BIPV (Building-Integrated Photovoltaics)

Solar materials built directly into building structures (e.g., solar shingles). Panel comparison calculator ›

DC-to-AC Ratio (ILR)

Array kWp divided by inverter kW — also called inverter loading ratio. Ratios of 1.1–1.3 are standard and usually optimal: slight midday clipping is traded for much better morning, evening and cloudy-day output. Above ~1.4, clipping losses and inverter input limits start to bite.

↑ Back to top

Inverters & Power Electronics

Solar Inverter

Electronic device converting DC power from panels/batteries into AC power for household appliances. Inverter sizing calculator ›

String Inverter

Centralized inverter converting power from a series string of solar panels. Inverter sizing calculator ›

Microinverter

Compact inverter mounted directly behind an individual solar panel to optimize panel-level power. Inverter sizing calculator ›

Power Optimizer

DC-to-DC converter on individual panels that maximizes output before sending power to a central inverter.

Hybrid Inverter

All-in-one inverter managing power from solar panels, battery storage, and the utility grid simultaneously. Inverter sizing calculator ›

Pure Sine Wave Inverter

Inverter outputting clean AC power identical to utility grid power, safe for sensitive electronics. Inverter sizing calculator ›

Modified Sine Wave Inverter

Low-cost inverter producing blocky AC output, causing humming or overheating in motors. Inverter sizing calculator ›

MPPT (Maximum Power Point Tracking)

Electronic circuit that dynamically tracks optimal voltage/current to maximize solar extraction. String sizing calculator ›

Inverter Clipping / DC/AC Ratio

Loss of potential solar power when DC array capacity exceeds inverter max AC output rating. String sizing calculator ›

Grid-Tied / On-Grid Inverter

Inverter that synchronizes voltage and frequency directly with the electrical utility grid. Inverter sizing calculator ›

Off-Grid Inverter

Standalone inverter operating independently of the grid, drawing power from battery banks. Inverter sizing calculator ›

Anti-Islanding Protection

Automatic safety mechanism shutting down grid-tied inverters during power outages to protect line workers. Inverter sizing calculator ›

Grid-Forming Inverter

Advanced inverter capable of creating its own local voltage frequency reference during grid outages. Inverter sizing calculator ›

Continuous Output Rating

Maximum power an inverter can continuously deliver without overheating or tripping. Inverter sizing calculator ›

Inverter Efficiency

Percentage of incoming DC power converted into usable AC power (typically 95%–98%). Inverter sizing calculator ›

No-Load Draw / Idle Consumption

Power consumed by an inverter simply remaining switched on with zero active loads. Inverter sizing calculator ›

Thd (Total Harmonic Distortion)

Measurement of output AC signal purity; lower THD means cleaner, safer power. Inverter sizing calculator ›

Transfer Speed / Switching Time

Time in milliseconds an inverter takes to switch from grid power to battery backup during blackouts. Inverter sizing calculator ›

Grid Feed-In Limit

Maximum AC wattage an inverter is legally or utility-permitted to export to the grid. Inverter sizing calculator ›

DC-to-AC Derating

Cumulative system power losses accounted for when calculating real AC output from DC panels. String sizing calculator ›

↑ Back to top

Batteries, Storage & Autonomy

Lithium Iron Phosphate (LiFePO₄ / LFP)

Thermally stable, ultra-long-life battery chemistry standard for solar storage. Battery bank calculator ›

Lead-Acid Battery

Traditional battery technology (AGM/Gel/Flooded) with lower upfront cost but shorter lifespan and low DoD. Battery bank calculator ›

NMC (Nickel Manganese Cobalt)

Compact lithium chemistry with high energy density, common in portable power stations and EVs. Battery bank calculator ›

Amp-Hour (Ah)

Measure of electric charge capacity in a battery (Ah × Voltage = Watt-hours). Battery bank calculator ›

Depth of Discharge (DoD)

Percentage of total battery capacity that has been discharged relative to total rated capacity. Battery bank calculator ›

State of Charge (SoC)

Remaining energy percentage available in a battery bank. Battery bank calculator ›

Days of Autonomy

Number of consecutive days a battery system can supply load demand without any solar or generator recharge. Battery bank calculator ›

Battery Management System (BMS)

Internal electronics monitoring cell voltages, temperature, balance, and over-current protection. Battery bank calculator ›

C-Rate

Speed at which a battery is charged or discharged relative to its total capacity rating (e.g., 1C, 0.5C). Battery bank calculator ›

Cycle Life

Total number of charge and discharge cycles a battery delivers before its total capacity drops to 80%. Battery runtime calculator ›

Thermal Runaway

Dangerous condition where internal battery heating leads to self-sustaining fire risk (rare in LFP). Battery runtime calculator ›

Low-Voltage Cutoff (LVC)

Threshold voltage at which a system disconnects loads to prevent permanent battery damage. Battery runtime calculator ›

Self-Discharge Rate

Natural power loss that occurs inside an idle battery over time when not connected to loads. Battery runtime calculator ›

Nominal Voltage

Standard operating voltage classification of a battery (e.g., 12V, 24V, 48V, or High Voltage 400V). Battery bank calculator ›

Usable Capacity

Actual energy in kWh available for use, factoring in maximum safe Depth of Discharge limits. Battery bank calculator ›

AC Coupling

Battery integration method where batteries connect to the system via a separate AC battery inverter. Battery bank calculator ›

DC Coupling

Battery integration method where solar panels charge batteries directly via a DC charge controller. Battery bank calculator ›

High Voltage (HV) Energy Storage

Battery systems operating above 100V DC (often 300V–400V) to reduce wiring losses. Battery bank calculator ›

Round-Trip Efficiency (RTE)

Percentage of energy retrieved from a battery relative to the total energy required to charge it. Battery bank calculator ›

Battery Bank

Multiple interlinked individual battery units wired in series, parallel, or series-parallel. Battery bank calculator ›

↑ Back to top

Generator & Emergency Power Sizing

Running Watts (Rated Watts)

Continuous electrical power needed to keep appliances operational after startup. Generator sizing calculator ›

Starting Watts (Surge Watts)

Extra temporary power needed by electric motor-driven loads during initial startup. Generator sizing calculator ›

Locked Rotor Amps (LRA)

Maximum current drawn by an electric motor when starting from a dead stop against full load pressure. Generator sizing calculator ›

Full Load Amps (FLA)

Operating current drawn by an electric motor under normal continuous load conditions. Generator sizing calculator ›

Standby Generator

Permanently installed back-up generator that starts automatically during power outages. Generator sizing calculator ›

Inverter Generator

Generator using digital electronics to produce clean AC power with variable engine speeds based on load. Inverter sizing calculator ›

Conventional Generator

Traditional mechanical generator running at fixed engine speeds (usually 3600 RPM) to maintain AC frequency. Generator sizing calculator ›

Dual-Fuel / Tri-Fuel Generator

Generator engineered to operate on gasoline, liquid propane (LPG), or natural gas (NG). Generator sizing calculator ›

Automatic Transfer Switch (ATS)

Electrical switch detecting grid failure and automatically transferring load to a backup system. Generator sizing calculator ›

Manual Transfer Switch (MTS)

Manually toggled switch isolating home circuits from the grid before connecting a generator. Generator sizing calculator ›

Interlock Kit

Mechanical safety device preventing main breaker and generator breaker from closing simultaneously. Generator sizing calculator ›

Suicide Cord

Extremely hazardous, non-compliant DIY male-to-male power cord used to backfeed a house (strictly banned). Generator sizing calculator ›

Power Inlet Box

Exterior weather-proof receptacle wired to a transfer switch where a generator cord plugs in. Generator sizing calculator ›

THD Penalty

Overheating risks imposed on sensitive electronics when powered by dirty utility or high-THD generators (>5%). Generator sizing calculator ›

Altitude Derating

Percentage drop in generator engine horsepower and watt output experienced as elevation increases above sea level. Generator sizing calculator ›

Temperature Derating

Reduction in electrical output capacity caused by high ambient operating temperatures. Generator sizing calculator ›

Fuel Derating

Power drop occurring when a generator runs on propane (~10%) or natural gas (~20%) instead of gasoline. Generator sizing calculator ›

Generator Runtime

Continuous hours a generator operates on a full fuel tank at specified load percentages. Generator sizing calculator ›

Soft Start Kit

Aftermarket electronic device installed on AC compressors to reduce LRA starting surge by up to 60–70%. Generator sizing calculator ›

NEMA Receptacle

Standardized physical plug and socket configuration scale (e.g., NEMA 14-50R, NEMA L14-30P). Generator sizing calculator ›

↑ Back to top

Electrical Wiring, Safety & Code Compliance

AWG (American Wire Gauge)

Standardized logarithmic wire size rating system (smaller AWG number indicates thicker wire). Wire size calculator ›

Voltage Drop

Loss of electrical voltage over cable run distances caused by electrical resistance in conductors. Voltage drop calculator ›

Series Circuit

Wiring method connecting positive to negative terminals; increases voltage while keeping amperage constant. Series/parallel calculator ›

Parallel Circuit

Wiring method connecting positive to positive terminals; increases amperage while keeping voltage constant. Series/parallel calculator ›

Series-Parallel Circuit

Combination wiring method used to scale both total system voltage and total current capacity. Series/parallel calculator ›

Charge Controller

DC regulator preventing solar panel arrays from overcharging battery banks. Charge controller calculator ›

PWM (Pulse Width Modulation)

Simple, lower-cost charge controller that pulls solar panel voltage down to match battery voltage. Charge controller calculator ›

Overcurrent Protection Device (OCPD)

Fuses or circuit breakers installed to protect wiring from thermal overload and fire. Wire size calculator ›

Rapid Shutdown System (RSS)

Safety requirement (NEC 690.12) de-energizing rooftop DC wiring within 30 seconds of shutdown.

DC Arc Fault Protection

Circuit protection identifying dangerous electric sparks across DC gaps to prevent fires (NEC 690.11).

Ground Fault Protection (GFPD)

System detecting unwanted current leaks flowing between energized conductors and ground.

Equipotential Grounding / Array Grounding

Bonding all metal panel frames and racking together to direct lightning surges safely to earth.

Ampacity

Maximum continuous current in amperes that an insulated conductor can carry safely without exceeding heat ratings. Wire size calculator ›

Conductor Temperature Rating

Maximum allowable operating temperature of wire insulation (e.g., 60°C, 75°C, 90°C THHN/THWN-2). Wire size calculator ›

Combiner Box

Enclosure where multiple solar string outputs are joined into a single main conductor feed. Wire size calculator ›

NEMA Enclosure Rating

Standard defining environmental protection levels for electrical boxes (e.g., NEMA 3R outdoor, NEMA 4X).

Subpanel / Critical Loads Panel

Secondary circuit breaker panel powering essential circuits during grid outages.

Busbar Rating

Maximum continuous current capacity of metal electrical strips inside a main breaker panel (e.g., 200A busbar). Wire size calculator ›

120% Rule (NEC 705.12)

Code limit dictating max backfed power allowed on a breaker panel: Solar Breaker + Main Breaker ≤ 120% × Busbar Rating. Wire size calculator ›

Conduit Fill

Maximum percentage of cross-sectional area inside electrical conduit permitted to be occupied by wires. Wire size calculator ›

Circular Mil (kcmil)

US unit for conductor cross-section: the area of a 1/1000-inch-diameter circle. Large cables above 4/0 AWG are sized in thousands of circular mils (kcmil); 1,000 kcmil ≈ 507 mm². Appears in ampacity tables and utility-scale wiring specs. AWG ↔ mm² converter ›

↑ Back to top

Utilities, Tariffs & Regional Incentives

Net Metering (NEM 1.0 / NEM 2.0)

Billing mechanism crediting solar owners at full retail electricity rates for exported energy. NEM 3.0 calculator ›

Net Billing (NEM 3.0)

Billing model crediting exported solar energy at wholesale avoided-cost rates rather than retail rates. NEM 3.0 calculator ›

Time-Of-Use (TOU) Rates

Utility pricing structure charging higher rates during peak demand hours (e.g., 4 PM–9 PM). NEM 3.0 calculator ›

Feed-In Tariff (FiT)

Guaranteed fixed payment rate paid by governments or utilities for renewable power fed to the grid. Germany solar calculator ›

PM Surya Ghar Muft Bijli Yojana

Indian government central subsidy program providing up to ₹78,000 for rooftop solar setups. India solar calculator ›

STC (Small-Scale Technology Certificate)

Australian federal solar subsidy based on system capacity, zone, and deeming year. Australia STC calculator ›

Federal Investment Tax Credit (ITC)

US federal tax credit (not a deduction) that offsets income tax owed. The 30% residential credit (Section 25D) applied to systems homeowners bought, but it was terminated for expenditures after 31 December 2025 under the 2025 One Big Beautiful Bill Act, so new residential purchases in 2026 no longer qualify. The separate commercial ITC (Sections 48E/45Y), used by businesses and third-party lease/PPA providers, continues on its own phase-down schedule. USA solar calculator ›

NEPRA Net Billing (SRO 251)

Pakistani net billing regulations defining buyback rates and prosumer grid integration rules. NEM 3.0 calculator ›

Smart Export Guarantee (SEG)

UK policy scheme requiring major energy suppliers to pay prosumers for exported solar power. UK solar calculator ›

Einspeisevergütung (EEG 2026)

Statutory German solar export remuneration scheme regulated under the Renewable Energy Sources Act. Germany solar calculator ›

Load-Shedding

Deliberate, rolling power outages initiated by utilities (e.g., Eskom in South Africa) to prevent total grid failure. South Africa calculator ›

Demand Charge

Utility fee assessed on commercial customers based on their single highest 15-minute energy peak in a billing cycle. Commercial solar calculator ›

Bi-Directional Meter

Smart electric meter measuring energy drawn from the grid and energy exported back to the grid. NEM 3.0 calculator ›

Interconnection Agreement

Legal contract between a solar system owner and the electric utility allowing grid connection. NEM 3.0 calculator ›

Avoided Cost

Wholesale price a utility saves by receiving solar power from prosumers rather than generating it themselves. NEM 3.0 calculator ›

Peak Shaving

Using solar or battery power to flatten high power draw spikes, reducing commercial demand charges. Commercial solar calculator ›

Self-Consumption Ratio

Percentage of generated solar energy consumed directly on-site rather than exported to the grid. Commercial solar calculator ›

Virtual Power Plant (VPP)

Network of decentralized home batteries aggregated by software to support the main grid during peaks. USA solar calculator ›

Prosumer

Electricity consumer who also produces power locally using solar or wind systems. USA solar calculator ›

Transformer Capacity Limit

Maximum total distributed solar wattage permitted on a local grid distribution transformer (e.g., 80% cap). USA solar calculator ›

DISCOM

India's state-level electricity distribution companies (e.g. MSEDCL, BESCOM, UPPCL). Your DISCOM sets the retail tariff, approves rooftop net-metering applications and credits exported units — which is why solar payback differs so much between Indian states.

RESCO

Renewable Energy Service Company model: a developer owns and maintains the rooftop system and sells you the power at a fixed per-unit rate, with zero capital cost to you. Common for Indian commercial and industrial buyers; the alternative is CAPEX (you buy the system outright). CAPEX vs RESCO calculator ›

Net-Metering Banking

The rules for how long exported units stay credited to your account before they lapse or are cashed out at a lower rate — monthly, quarterly or annual settlement depending on the state or utility. Short banking periods penalise systems that overproduce in one season.

Export Limit

A cap the utility places on how much power your inverter may push into the grid, sometimes zero ("zero-export"). Enforced in firmware, it can clip savings for oversized arrays, so check it before sizing beyond your daytime self-consumption.

Duck Curve

The demand-minus-solar curve utilities see: a midday trough as rooftop solar floods the grid, then a steep evening ramp. It is why export rates keep falling at midday and why batteries and evening self-consumption are increasingly rewarded.

PM-KUSUM

India's farm-solar scheme: subsidised standalone solar pumps (Component B) and solarised grid-connected pumps (Component C), with central + state subsidies typically covering 60%+ of cost. KUSUM pump calculator ›

↑ Back to top

High-Load Appliances & Electrification

BTU (British Thermal Unit)

Energy unit measuring heating and cooling capacity (12,000 BTU/hr = 1 Ton of Cooling). Mini-split calculator ›

Mini-Split Heat Pump

Ductless heating/cooling system featuring high efficiency and variable inverter compressor draw. Mini-split calculator ›

SEER2 (Seasonal Energy Efficiency Ratio 2)

Updated efficiency metric for heat pumps and air conditioners over an entire cooling season. Mini-split calculator ›

Level 1 EV Charger

Standard 120V EV charging cable plugging into standard wall outlets (draws ~1.2 kW–1.4 kW). EV charging calculator ›

Level 2 EV Charger

Fast 240V AC EV charger drawing between 16 Amps to 48 Amps (~3.8 kW to 11.5 kW). EV charging calculator ›

Level 3 DC Fast Charger

Commercial high-voltage DC charger supplying 50 kW to 350+ kW directly to an EV battery. EV charging calculator ›

Heat Pump Water Heater

Ultra-efficient electric water heater using a heat pump to extract heat from surrounding air. Mini-split calculator ›

Induction Cooktop

Electric stove using electromagnetic energy to heat iron cookware directly with high instantaneous wattage. Load calculator ›

Submersible Well Pump

High-torque electric pump located deep underwater inside a well casing; carries high LRA surge. Well pump calculator ›

Sump Pump

Motorized pump installed in a basement pit to remove accumulated water during storms. Well pump calculator ›

Whole-Home Electrification

Transitioning a house from fossil fuels (gas/oil) to all-electric appliances powered by solar. Home electrification calculator ›

Load Aggregation

Total combined running and surge wattage requirement when running multiple heavy appliances simultaneously. Load calculator ›

Smart Plug / Energy Monitor

Monitoring device (e.g., Emporia Vue, Sense) measuring exact real-time circuit power usage. Load calculator ›

Coefficient of Performance (COP)

Efficiency ratio of heating/cooling delivered relative to electrical energy consumed. Mini-split calculator ›

Continuous Duty Cycle

Operating condition where an appliance runs at full rated load continuously for 3 hours or more. Load calculator ›

Duty Cycle Percentage

Percentage of time an appliance motor operates versus standing idle during a given cycle. Panel comparison calculator ›

Resistive Load

Simple electrical load without motors or magnets (e.g., space heater, toaster) where power factor is 1.0. Load calculator ›

Inductive Load

Electrical load containing wire coils and motors (e.g., AC compressor, pump) creating electromagnetic resistance and surge. Load calculator ›

Capacitive Load

Circuit load that stores energy in electrostatics (e.g., large electronic power supplies, LED drivers). Load calculator ›

Staggered Motor Starting

Operational sequence turning heavy motor loads on one by one to avoid stacking startup surges. Load calculator ›

Ton of Refrigeration (TR)

Cooling unit equal to 12,000 BTU/hr (~3.5 kW of heat moved) — historically, melting one US ton of ice in 24 hours. A 1.5-ton AC delivers ~5.3 kW of cooling while drawing 1.2–1.9 kW of electricity depending on efficiency; always size solar from the electrical draw. BTU ↔ kW ↔ tons converter ›

BEE Star Rating

India's appliance efficiency label from the Bureau of Energy Efficiency. For ACs, each extra star cuts roughly 8–12% of annual consumption — a 5-star 1.5-ton inverter AC draws about 1.2–1.4 kW versus ~1.9 kW for an old 2-star unit, which directly shrinks the solar and battery needed to run it.

Sanctioned Load

The maximum demand (kW or kVA) your electricity connection is contracted for. In India it caps the rooftop capacity most DISCOMs will approve for net metering (often 100% of sanctioned load, sometimes less), so upgrading it can be a prerequisite for a bigger array.

↑ Back to top

Mobile, Off-Grid & RV Solar Systems

Shore Power

External AC grid power supplied to an RV, boat, or camper van via an exterior outlet plug. RV / van solar calculator ›

Portable Power Station

Self-contained mobile unit housing an LFP battery, BMS, solar charge controller, and AC inverter. RV / van solar calculator ›

Flexible Solar Panel

Thin, lightweight panel engineered to bend slightly to conform to curved RV or boat roofs. RV / van solar calculator ›

Rigid Glass Panel

Traditional aluminum-framed glass solar panel designed for maximum durability and thermal airflow. RV / van solar calculator ›

Smart Shunt

Precision battery monitor measuring exact Current (Amps) flowing in and out of a battery bank via a resistor. RV / van solar calculator ›

DC-to-DC Charger

Charger taking power from a vehicle's alternator to safely charge an auxiliary house battery while driving. RV / van solar calculator ›

Alternator Charging

Charging an RV or boat battery bank using excess mechanical power from the vehicle engine's alternator. RV / van solar calculator ›

Marine Grade Cable

Tinned copper wire engineered to resist corrosion and oxidation in salt-water or humid environments. RV / van solar calculator ›

RV Rooftop AC

Compact 120V AC unit mounted on RV roofs (typically rated at 13,500 BTU or 15,000 BTU). RV / van solar calculator ›

Solar Port / SAE Inlet

Exterior pre-wired socket installed on trailers allowing quick connection of suitcase solar panels. RV / van solar calculator ›

Lug Terminal / Cable Ring

Crimp connector attached to heavy gauge copper wires for securing to battery posts or busbars.

Busbar Disconnect Switch

Rotary safety switch isolating the entire battery bank or DC system during maintenance or storage.

Anderson Powerpole

Genderless, high-current quick-connect plug format popular in mobile, amateur radio, and DC setups.

Grounding Rod

Copper electrode driven into the earth to establish a ground reference for off-grid power systems.

Pure DC System

Off-grid setup running purely on 12V/24V/48V DC equipment without any AC inverter losses.

Inverter Remote Switch

Wall-mounted or app-connected switch allowing remote toggling of off-grid inverters. Inverter sizing calculator ›

Vibration Resistance

Engineering rating measuring an electrical component's ability to survive constant road vibration.

Ground Loop

Unwanted current flow occurring when an electrical system has multiple ground paths at slightly different potentials.

High-Draw DC Load

Equipment drawing massive DC amperage (e.g., 12V electric winches, high-power windlasses).

Star Ground / Single-Point Ground

Wiring configuration where all system grounds connect to one centralized busbar location.

↑ Back to top

Financial Sizing, Economics & Carbon Offsets

Return On Investment (ROI)

Percentage metric evaluating financial gain generated by a solar setup relative to its total cost. Savings & payback calculator ›

Payback Period

Number of years required for electricity bill savings to equal the initial net cost of a solar system. Savings & payback calculator ›

Levelized Cost of Energy (LCOE)

Total lifetime cost of installing and maintaining a solar system divided by total lifetime kWh output. Savings & payback calculator ›

Internal Rate of Return (IRR)

Financial metric calculating the annual compound return rate generated by a solar investment. Savings & payback calculator ›

Net Present Value (NPV)

Value of future electricity bill savings discounted to present-day currency value. Savings & payback calculator ›

Cost Per Watt ($/W or ₹/W)

Standard pricing metric dividing total system installation cost by total DC solar panel capacity. Savings & payback calculator ›

CAPEX (Capital Expenditure)

Total upfront cash outlay required to purchase and install a solar or battery system. Commercial solar calculator ›

OPEX (Operational Expenditure)

Ongoing maintenance, cleaning, fuel, and insurance costs over a system's lifespan. Commercial solar calculator ›

Accelerated Depreciation

Tax rule allowing businesses to write off a major percentage of solar asset value in year 1 (e.g., 40% in India). Commercial solar calculator ›

Power Purchase Agreement (PPA)

Financing contract where a third party owns the solar panels and sells generated power back at a fixed rate. Savings & payback calculator ›

Solar Lease

Agreement where a homeowner pays a fixed monthly rental fee to use solar panels owned by a third party. Savings & payback calculator ›

Solar Loan EMI

Equated Monthly Installment paid to a bank when financing solar system equipment purchases. Solar loan EMI calculator ›

Cash Flow Positive

Condition where monthly electricity bill savings exceed the monthly EMI payment on a solar loan. Solar loan EMI calculator ›

Carbon Offset / Carbon Footprint

Reduction in greenhouse gas emissions achieved by displacing fossil-fuel grid electricity with solar. Carbon offset calculator ›

Metric Tons of CO₂ Equivalent

Standard international unit for greenhouse-gas reduction. The CO₂ a solar system offsets depends on the local grid mix: roughly 0.4 t CO₂/MWh on cleaner grids (US average) up to 0.7–0.9 t CO₂/MWh on coal-heavy grids such as India.

EPA Greenhouse Gas Equivalencies

Conversions translating solar kWh production into concrete metrics (e.g., trees planted, miles driven). Carbon offset calculator ›

SREC (Solar Renewable Energy Certificate)

Tradable environmental certificate earned for every 1,000 kWh of solar energy generated. Carbon offset calculator ›

Degradation Cost Penalty

Financial loss calculated into long-term models as panel efficiency drops by ~0.5% each year. Savings & payback calculator ›

Utility Inflation Rate

Annual percentage rate at which grid electricity prices rise (typically 3%–6% annually). Savings & payback calculator ›

Net Financial Savings

Cumulative 25-year financial profit remaining after subtracting total CAPEX and OPEX from lifetime bill savings. Savings & payback calculator ›

↑ Back to top

No terms match your search. Try a shorter keyword.