Off-the-gridOff-the-grid or off-grid is a characteristic of buildings and a lifestyle designed in an independent manner without reliance on one or more public utilities. The term "off-the-grid" traditionally refers to not being connected to the electrical grid, but can also include other utilities like water, gas, and sewer systems, and can scale from residential homes to small communities. Off-the-grid living allows for buildings and people to be self-sufficient, which is advantageous in isolated locations where normal utilities cannot reach and is attractive to those who want to reduce environmental impact and cost of living.
Variable renewable energyVariable renewable energy (VRE) or intermittent renewable energy sources (IRES) are renewable energy sources that are not dispatchable due to their fluctuating nature, such as wind power and solar power, as opposed to controllable renewable energy sources, such as dammed hydroelectricity or biomass, or relatively constant sources, such as geothermal power. The use of small amounts of intermittent power has little effect on grid operations. Using larger amounts of intermittent power may require upgrades or even a redesign of the grid infrastructure.
Virtual power plantA virtual power plant (VPP) is a cloud-based distributed power plant that aggregates the capacities of heterogeneous distributed energy resources (DER) for the purposes of enhancing power generation, trading or selling power on the electricity market, and demand side options for load reduction. DER assets in a VPP can include photovoltaic solar, energy storage, electric vehicle chargers, and demand-responsive devices (such as water heaters, thermostats, and appliances) with examples of virtual power plants existing in the United States, Europe, and Australia.
Utility submeterUtility sub-metering is a system that allows a landlord, property management firm, condominium association, homeowners association, or other multi-tenant property to bill tenants for individual measured utility usage. The approach makes use of individual water meters, gas meters, or electricity meters. Sub-metering may also refer to the monitoring of the electrical consumption of individual equipment within a building, such as HVAC, indoor and outdoor lighting, refrigeration, kitchen equipment and more.
Solar inverterA solar inverter or photovoltaic (PV) inverter is a type of power inverter which converts the variable direct current (DC) output of a photovoltaic solar panel into a utility frequency alternating current (AC) that can be fed into a commercial electrical grid or used by a local, off-grid electrical network. It is a critical balance of system (BOS)–component in a photovoltaic system, allowing the use of ordinary AC-powered equipment.
Duck curveThe duck curve is a graph of power production over the course of a day that shows the timing imbalance between peak demand and solar power generation. Used in utility-scale electricity generation, the term was coined in 2012 by the California Independent System Operator. In some energy markets, daily peak demand occurs after sunset, when solar power is no longer available.
Demand responseDemand response is a change in the power consumption of an electric utility customer to better match the demand for power with the supply. Until the 21st century decrease in the cost of pumped storage and batteries electric energy could not be easily stored, so utilities have traditionally matched demand and supply by throttling the production rate of their power plants, taking generating units on or off line, or importing power from other utilities.
Grid-tied electrical systemA grid-tied electrical system, also called tied to grid or grid tie system, is a semi-autonomous electrical generation or grid energy storage system which links to the mains to feed excess capacity back to the local mains electrical grid. When insufficient electricity is available, electricity drawn from the mains grid can make up the shortfall. Conversely when excess electricity is available, it is sent to the main grid.
Grid-connected photovoltaic power systemA grid-connected photovoltaic system, or grid-connected PV system is an electricity generating solar PV power system that is connected to the utility grid. A grid-connected PV system consists of solar panels, one or several inverters, a power conditioning unit and grid connection equipment. They range from small residential and commercial rooftop systems to large utility-scale solar power stations. When conditions are right, the grid-connected PV system supplies the excess power, beyond consumption by the connected load, to the utility grid.
MicrogenerationMicrogeneration is the small-scale production of heat or electric power from a "low carbon source," as an alternative or supplement to traditional centralized grid-connected power. Microgeneration technologies include small-scale wind turbines, micro hydro, solar PV systems, microbial fuel cells, ground source heat pumps, and micro combined heat and power installations. These technologies are often combined to form a hybrid power solution that can offer superior performance and lower cost than a system based on one generator.