German power plants communicate with each other and coal power can go to 50% capacity in 15 minutes, during which the excess power can be sucked up by pumped hydro, for <1 minute long deviations there is enough battery and flywheel storage too. And most people in Germany have utility-controlled tank water heaters, which can be turned on not just at fixed hours but also based on the grid status (this causes the meters to go into Low-Tariff mode too), and sometimes even smart thermostats, enabling remote load management.
In emergency power excess, solar can go off grid safely or brakes can be applied to wind turbines, which wastes power but is preferred to overheating transformers due to higher mains frequency (yes, power overproduction causes the frequency to go up, not so much the voltage).
But maybe the coal lobby keeps convincing the distributor that operating plants below 80% doesn’t do their workers justice, or some nonsense like that
Oh boy, you just triggered my nerd infodump mode. Brace yourself.
Disclaimer: I only researched the practical applications in the Czech Republic. I’d guess Slovakia’s situation is 99% similar, the neighboring Germany is 95% similar (just with more solar and no nuclear power) and most of Europe is 80% similar (with varying energy mixes). Similarly to Teletext, I am pretty sure Alec from Technology Connections (YouTuber from Chicago) would have made a video on this if it was widespread where he lives.
Basically yes. Residential boilers in Germany are part of load management.
Technically, the electric water heaters themselves are not “smart” in any way, they are just resistors and thermostats in a water tank. The “smartest” units you’ll find use a decades-old trick with two thermostats and heating filaments to achieve a larger virtual tank size. Turn them on, and they’ll do their best to maintain a steady 70 °C (or whatever) at the output. Similarly, gas furnaces are all rather dumb too. There are two contacts on the units; bridge them to allow at most 100 mA to flow, which will energize a contactor (big relay) to switch the heating element or signal to the furnace electronics to go through the ignition routine. Air conditioners typically have another contact for cooling.
This is great: the protocol basically every heater uses could not be simpler and that allows anyone to build a thermostat, so available products range from the most basic bimetallic units (temperature knob and manual day (T)/night (T–5°C)/off switch) to AI Smart Home Automation IoT Buzzword Salad™ devices. The most common kind nowadays has two AA cells, a thermistor, a simple LCD display, rubber buttons to temporarily adjust the temperature manually, and a flap to reveal more buttons that set the time and weekday, create the weekly temperature schedule, adjust hysteresis, start Vacation Mode etc. There is either a set of wired contacts and a latching relay for the aforementioned wired “protocol”, or a wireless transmitter that controls a wall-plug-based receiver close to the furnace.
However, a ripple control system receiver can be connected in series to the thermostat, only allowing heating at certain times set in your energy contract. Or more often, people hook it up to the boiler. All energy you consume at these times is metered separately and up to 2x cheaper so the system saves you money at rare discomfort, you can use a switch to override it at any time if you accept the extra cost.
Various companies use ripple control system receivers for energy intensive, time-independent operations, such as
water tower pumps
baking, annealing furnaces
computationally heavy tasks (rendering)
heating water for swimming pools
charging electric vehicles
All such uses have different tariffs, hours (plus limits to unscheduled switches) and thus need different RCS channels. Also, RCS receivers can control municipal lighting etc.
First dual-tariff systems used switching clocks inside the tamper-proof electric meter. This did not allow for regulation so that a simple device with mechanical logic (rotary decoder of series signal) was introduced, where a starting tone (3 seconds of an approx. 250 Hz “tone” on top of the mains voltage) followed by series of 44 gaps or tones (1 second long, 0.5 s apart) that singalled on/off states for each of the 44 channels. This was later revised into a “1 of 4” + “1 of 8” coding for 32 device groups, each then having 16 channels controlled by 2 bits each, with “10” meaning ON, “01” meaning OFF, any other means ERROR; ABORT RECEPTION. This division of the 44 pulses into groups of 4+8+2x16 allowed for 512 channels and more robustness. This protocol from the 1980s is used to this day, and so is a similar one in Germany called DECABIT. The later VERSACOM, used in both countries, then uses proprietary licenced data schemes with up to 128 bits and allows addressing individual customers. It always starts with 4 “1” bits so that dumb receivers expecting a “1 of 4” code (0001, 0010, 0100 or 1000) abort reception. VERSACOM receivers have clocks synced by special transmissions and keep a regularly broadcast weekly schedule in memory so that the bandwidth is free for the old protocol commands at switching times. Every household is assigned one of the 512+ channels and these groups switch minutes apart to prevent jumps in mains load.
I NEED A NAP. THE COMMENT WILL BE FINISHED IN A FEW HOURS.
OK, I’m going to save you time because I do some controls and totally get how “easy” demand management should be given how simple most devices are.
But WHAT?! Thats all built into the grid over there??? That’s AWESOME. Let me see if I have this right: there’s essentially a small transient frequency modulation in the 60hz(?) in the grid that allows devices to receive a “off” signal?
I could be wrong but I’m 90% sure we’ve got nothing like that in the states. MAYBE there’s something like that for communicating with the meter itself but certainly not past the meter.
The nuclear reactor shutdowns were a push by the Greens in the early years of this millennium. Probably the biggest change they succeeded with in German politics, so that tells you a lot about the quality of that “party”.
Stop burning coal then
German power plants communicate with each other and coal power can go to 50% capacity in 15 minutes, during which the excess power can be sucked up by pumped hydro, for <1 minute long deviations there is enough battery and flywheel storage too. And most people in Germany have utility-controlled tank water heaters, which can be turned on not just at fixed hours but also based on the grid status (this causes the meters to go into Low-Tariff mode too), and sometimes even smart thermostats, enabling remote load management.
In emergency power excess, solar can go off grid safely or brakes can be applied to wind turbines, which wastes power but is preferred to overheating transformers due to higher mains frequency (yes, power overproduction causes the frequency to go up, not so much the voltage).
But maybe the coal lobby keeps convincing the distributor that operating plants below 80% doesn’t do their workers justice, or some nonsense like that
… Consumer water heaters in Germany are built in as demand shaving??? That is so damn cool.
Oh boy, you just triggered my nerd infodump mode. Brace yourself.
Disclaimer: I only researched the practical applications in the Czech Republic. I’d guess Slovakia’s situation is 99% similar, the neighboring Germany is 95% similar (just with more solar and no nuclear power) and most of Europe is 80% similar (with varying energy mixes). Similarly to Teletext, I am pretty sure Alec from Technology Connections (YouTuber from Chicago) would have made a video on this if it was widespread where he lives.
Basically yes. Residential boilers in Germany are part of load management.
Technically, the electric water heaters themselves are not “smart” in any way, they are just resistors and thermostats in a water tank. The “smartest” units you’ll find use a decades-old trick with two thermostats and heating filaments to achieve a larger virtual tank size. Turn them on, and they’ll do their best to maintain a steady 70 °C (or whatever) at the output. Similarly, gas furnaces are all rather dumb too. There are two contacts on the units; bridge them to allow at most 100 mA to flow, which will energize a contactor (big relay) to switch the heating element or signal to the furnace electronics to go through the ignition routine. Air conditioners typically have another contact for cooling.
This is great: the protocol basically every heater uses could not be simpler and that allows anyone to build a thermostat, so available products range from the most basic bimetallic units (temperature knob and manual day (T)/night (T–5°C)/off switch) to AI Smart Home Automation IoT Buzzword Salad™ devices. The most common kind nowadays has two AA cells, a thermistor, a simple LCD display, rubber buttons to temporarily adjust the temperature manually, and a flap to reveal more buttons that set the time and weekday, create the weekly temperature schedule, adjust hysteresis, start Vacation Mode etc. There is either a set of wired contacts and a latching relay for the aforementioned wired “protocol”, or a wireless transmitter that controls a wall-plug-based receiver close to the furnace.
However, a ripple control system receiver can be connected in series to the thermostat, only allowing heating at certain times set in your energy contract. Or more often, people hook it up to the boiler. All energy you consume at these times is metered separately and up to 2x cheaper so the system saves you money at rare discomfort, you can use a switch to override it at any time if you accept the extra cost.
Various companies use ripple control system receivers for energy intensive, time-independent operations, such as
All such uses have different tariffs, hours (plus limits to unscheduled switches) and thus need different RCS channels. Also, RCS receivers can control municipal lighting etc.
First dual-tariff systems used switching clocks inside the tamper-proof electric meter. This did not allow for regulation so that a simple device with mechanical logic (rotary decoder of series signal) was introduced, where a starting tone (3 seconds of an approx. 250 Hz “tone” on top of the mains voltage) followed by series of 44 gaps or tones (1 second long, 0.5 s apart) that singalled on/off states for each of the 44 channels. This was later revised into a “1 of 4” + “1 of 8” coding for 32 device groups, each then having 16 channels controlled by 2 bits each, with “10” meaning ON, “01” meaning OFF, any other means ERROR; ABORT RECEPTION. This division of the 44 pulses into groups of 4+8+2x16 allowed for 512 channels and more robustness. This protocol from the 1980s is used to this day, and so is a similar one in Germany called DECABIT. The later VERSACOM, used in both countries, then uses proprietary licenced data schemes with up to 128 bits and allows addressing individual customers. It always starts with 4 “1” bits so that dumb receivers expecting a “1 of 4” code (0001, 0010, 0100 or 1000) abort reception. VERSACOM receivers have clocks synced by special transmissions and keep a regularly broadcast weekly schedule in memory so that the bandwidth is free for the old protocol commands at switching times. Every household is assigned one of the 512+ channels and these groups switch minutes apart to prevent jumps in mains load.
I NEED A NAP. THE COMMENT WILL BE FINISHED IN A FEW HOURS.
OK, I’m going to save you time because I do some controls and totally get how “easy” demand management should be given how simple most devices are.
But WHAT?! Thats all built into the grid over there??? That’s AWESOME. Let me see if I have this right: there’s essentially a small transient frequency modulation in the 60hz(?) in the grid that allows devices to receive a “off” signal?
I could be wrong but I’m 90% sure we’ve got nothing like that in the states. MAYBE there’s something like that for communicating with the meter itself but certainly not past the meter.
The nuclear reactor shutdowns were a push by the Greens in the early years of this millennium. Probably the biggest change they succeeded with in German politics, so that tells you a lot about the quality of that “party”.