only receives around a half of the domestic retail rate, because the German system pays what each source costs (including a reasonable profit margin). Virtual net metering Another method of producing power to the grid is through virtual net metering (also called peer-to-peer (P2P) energy trading, wheeling and sometimes local energy trading). Peer-to-peer energy trading is a novel paradigm of power system operation, where sellers can generate their own energy in dwellings, offices and factories, and share it with each other locally. Several companies offering virtual net metering use blockchain technology. Related technology Sources that produce direct current, such as solar panels, must be coupled with an electrical inverter to convert the output to alternating current for use with conventional appliances. The phase of the outgoing power must be synchronized with the grid, and a mechanism must be included to disconnect the feed in the event of grid failure. This is for safety for example, workers repairing downed power lines must be protected from "downstream" sources, in addition to being disconnected from the main "upstream" distribution grid. Although a small generator lacks the power to energize a loaded line, this can happen if the line is isolated from other loads. Solar inverters are designed for safety while one inverter could not energize a line, a thousand might. In addition, electrical workers are trained to treat every line as though it was live, even when they know it should be safe. Solar guerrilla Solar guerrilla (or the guerrilla solar movement) is a term originated by Home Power Magazine and is applied to someone who connects solar panels without permission or notification and uses monthly net metering without regard for law. See also Automatic meter reading Demand response Electricity meter Home energy upgrades from public utilities Interstate Renewable Energy Council Off-the-grid Power system automation Smart grid Uninterruptible power supply Utility submeter Variable pricing Virtual power plant Notes References External links Virtual Net Metering - California Public Utilities Commission. Renewable energy policy Renewable energy economy Energy storage Pricing