Just to intensify the feeling of impending zombie apocalypse of the COVID-19 lockdown in the British countryside where I live, we had a power cut. It’s not an uncommon occurrence here at the end of a long rural power distribution network, and being prepared for a power outage is something I wrote about a few years ago. But this one was a bit larger than normal and took out much more than just our village. I feel very sorry for whichever farmer in another village managed to collide with an 11kV distribution pole.
What pops to mind for today’s article is the topic of outage monitoring. When plunged into darkness we all wonder if the power company knows about it. The most common reaction must be: “of course the power company knows the power is out, they’re the ones making it!”. But this can’t be the case as for decades, public service announcements have urge us to report power cuts right away.
In our very modern age, will the grid become smart enough to know when, and perhaps more importantly where, there are power cuts? Let’s check some background before throwing the question to you in the comments below.
Continue reading “Ask Hackaday: Is Our Power Grid Smart Enough To Know When There’s No Power?”
[Aleksejs Mirnijs] needed a tool to accurately measure the power consumption of his Raspberry Pi and Arduino projects, which is an important parameter for dimensioning adequate power supplies and battery packs. Since most SBC projects require a USB hub anyway, he designed a smart, WiFi-enabled 4-port USB hub that is also a power meter – his entry for this year’s Hackaday Prize.
[Aleksejs’s] design is based on the FE1.1s 4-port USB 2.0 hub controller, with two additional ports for charging. Each port features an LT6106 current sensor and a power MOSFET to individually switch devices on and off as required. An Atmega32L monitors the bus voltage and current draw, switches the ports and talks to an ESP8266 module for WiFi connectivity. The supercharged hub also features a display, which lets you read the measured current and power consumption at a glance.
Unlike most cheap hubs out there, [Aleksejs’s] hub has a properly designed power path. If an external power supply is present, an onboard buck converter actively regulates the bus voltage while a power path controller safely disconnects the host’s power line. Although the first prototype is are already up and running, this project is still under heavy development. We’re curious to see the announced updates, which include a 2.2″ touchscreen and a 3D-printable enclosure.
More and more, the power grid is distributed. Houses have solar panels on their roofs, and where possible, that excess power is sold back to the grid. The current trend is towards smart meters that record consumption for an entire household and relay it back to the power plant every day or so. The future is decentralized, through, and a meter that is smart once a day simply won’t do. A team on Hackaday.io has put together the ultimate in decentralized energy modernization. It’s the InternetS of Energy, and it removes the need for power companies completely.
The team has identified a few key features of the current power grid that don’t make sense in the age of the Internet. The power company doesn’t have extremely granular data, and sending power over long distances is either inefficient or expensive. The solution for this is to have distributed power plants, all connected together into a truly intelligent power grid.
This InternetS of Energy uses open-source energy monitoring systems running the Ethereum client to push power-usage data onto the blockchain. This makes the grid secure and pseudonymous, and if the banking industry is any indication, something like this is the future of economic transactions.
While it may not be the best solution for mature power grids, it is an extremely interesting avenue of research for developing nations. Wherever local resources allow it, electricity can be generated and sent to where it’s needed. It’s exactly what the power grid would be if it were re-designed today from scratch, and an excellent candidate for the 2016 Hackaday Prize.
The only useful data you’ll ever find is already digitized, but a surprising number of gauges and meters are still analog. The correct solution to digitizing various pressure gauges, electric meters, and any other analog gauge is obviously to replace the offending dial with a digital sensor and display. This isn’t always possible, so for [Egar] and [ivodopiviz]’s Hackaday Prize entry, they’re coming up with a way to convert these old analog gauges to digital using a Raspberry Pi and a bit of computer vision.
The idea behind this instrument digitizer isn’t to replace the mechanics and electronics, as we are so often wont to do. Instead, this team is using a 3D printed bracket that mounts a Raspberry Pi and camera directly in front of an analog gauge. Combine this contraption with OpenCV, and you have a device that’s just smart enough to look at a needle on a dial, convert that to a number, and save it to a file or send it out over WiFi.
It’s an extremely simple device for what [Egar] and [ivodopiviz] admit is a relatively niche application. However, if you only need digital measurements of an analog meter for a month or so, or you don’t want to mess up your steampunk decor, it’s an ingenious build.
The Internet of Things has been applied to toasters, refrigerators, Christmas lights, Barbies, and socks. Unsurprisingly, the Internet of Things has yet to happen – that would require a useful application of putting the Internet in random devices. One of the best ideas is a smart electric meter, but the idea behind this is to give the power company information on how much electricity you’re using, not give you an idea of how much power you’re pulling down. The answer to this is the Internet-enabled Kill-A-Watt, and that’s exactly what [Solenoid] is building for his entry into the Hackaday Prize.
Modern power meters have an LED somewhere on the device that blinks every time a Watt is used. This is the data [Solenoid]’s creation is pushing up to the Internet to relay power consumption to himself or anyone else in the world.
The hardware, like many upcoming Hackaday Prize entries, we’re sure, is based on the ESP8266 WiFi module, with a light sensor, SD card reader, and OLED display. It’s meant to mount directly to a power meter, recording power consumption and pushing that data up the network. It’s simple, but it also allows for very granular monitoring of [Solenoid]’s power consumption, something the electric company’s smart meters can’t compete with.
With tiny, Internet-connected computers everywhere these days, home automation is finally hitting it big. [Jelora] was looking for a few more home automation projects and realized his electric meter had a pair of ‘digital information outputs’. With a Raspberry Pi and a few bits of wire, he figured out how to read this digital output and put a log of his electricity consumption up on the web.
The digital output on [Jelora]’s meter is a bit odd; it’s 1200 bps, 7 bits per character, parity, with one stop bit. It’s also a 50 kHz AC signal for a binary ‘0’ and nothing for a binary ‘1’. To read this signal, [Jelora] is using a diode to throw out half the signal, a 6N138 optoisolator so the Pi isn’t connected directly to the meter, and a small cap to smooth out the signal. Simple, and it works.
This cleaned up signal is then connected to serial to USB chip and a PHP script scrapes the data every minute. The data received from the meter is stored in a data base along with a few other bits of information: if the meter is being charged peak or off-peak rates, and the price per kWh. All this is saved on an IDE hard drive (more reliable than the SD card, surprisingly), and a ‘electricity cost per day’ is plotted on a nifty graph and served up by the Raspberry Pi.
For his masters at Cornell, [Christopher McNally] designed a simple, non intrusive home power meter capable of doing everything a ‘smart meter’ can do – log power consumption throughout a home, and display a log of a home’s power consumption over WiFi. He’s even testing out some interesting ideas, like automatically detecting when specific devices turn on by reading the current data.
From [Chris]'[Jeramy] developed his system around the Arduino and a Ethernet shield, taking care of networking and choosing a micro, leaving him more time to develop the more interesting part of the project: sensing current. For this he used a small, clip-on current transducer. This sensor generates up to 10 VAC across a resistor, but the Arduino doesn’t play well with AC, requiring a small rectifier built around an op amp.
While the project works as a homebrew smart meter, [Jeramy] wasn’t able to automatically detect when certain devices were powered on. This is partly due to the fact that changes in current were only seen in magnitude and not waveform. Also, if two devices were powered on at the same time, the software would see that as a larger device that draws the sum of the current of two smaller devices. Still, [Jeramy] came up with a cheap way of metering power in any home, and the cost of his solution is cheaper than a lot of professional systems out there.
All the code, files, and design report are available on [Jeramy]’ git.