Technology To Send Messeges Through Electricity Cables To Any Device

[John Lewis]

The new data system, created using telecoms technology by Reactive Technologies (RT) and now successfully tested on the UK's National Grid, could allow the optimum use of intermittent renewable energy, an important feature given the fast-rising proportion of green energy on the grid.

Unlike the smart meters being rolled out by the UK government, the new system is anonymous, with no data on household energy use being collected and therefore avoiding concerns about privacy.

The system uses new technology to send messages through national electricity cables to any appliances with a smart plug connected to the mains, asking it to adjust its energy use. In the home, this could mean allowing the temperature of a freezer to increase by 0.5C to cut demand or turning up a water heater at 1am to utilise spare renewable energy.

"The old mindset would be, we need to build more power stations," said Jens Madrian (https://www.theguardian.com/environment/2016/oct/11/energy-first-as-uk-successfully-transmits-data-via-national-electricity-grid), at RT and former CFO at "big six" utility RWE npower. "We disagree with that. There are other ways of managing electricity, one of which is carrying knowledge from the telecommunications and software engineering side into the energy sector."

[Rob Beckers]

John, this is generally what's understood as the future "smart grid". There no longer are just passive produces and consumer of electricity, but an intelligent grid management system can move power around, cause loads to ramp up and down (to a point) etc. It will allow for much better matching of supply and demand, and deal better with extremes (shed loads when needed etc.).

Interesting stuff!

-RoB-

[John Lewis]

Hi Rob,
Thanks for the info. Is this technology already in place in UK or in any other part of the world. Would like to know more about this.

[Dave Schwartz]

This is interesting. I looked at the linked article and see that the key feature in this technology is that their solution to the problem of signal propagation over the grid is to run the signal at the same frequency as the grid.

Data over power lines has been around for quite a while. I have two such implementations in my home: an ethernet-over-powerline extension to an observatory in my back yard (where WiFi was too unreliable) and several of my satellite TV receivers without ethernet connections talk over the powerline to the one that does. The problem with high (useful) data rates over power lines is that the signal does not survive beyond the closest transformer to your house because grid transformers do not pass signals at those frequencies.

So this company has developed a way to detect a mains-frequency signal superimposed on the mains sine wave itself. At 50 or 60 Hz, the data rate would be incredibly low (and the protocol to deal with the massive amount of noise that must be there too would lower it even more) so there would likely be no useful way to target individual devices, households or probably even relatively small areas (and a device would need to know where it was even for that to work).

At the residential level, the effect would have to be quite small and have a random effect. Imagine the power surge that would result if there was a very hot day, hundreds of thousands of central air conditioners were running, they all received the 'conserve' signal and all decide to shut off at once. Conversely, a large brownout if all the EV chargers act on the same 'OK to charge now' signal in the middle of the night. So there are still lots of challenges even after you solve the data transmission problem.

We do have (had?) a somewhat similar system here in Ontario (and maybe a few other places) called Peaksaver Plus. These systems are called 'Demand Response (DR)' systems. The idea was that you would have a special thermostat installed that could be addressed when there was a situation that required a demand reduction during a peak emergency. This was targeted to reduce air conditioning loads by increasing thermostat set points a few degrees for the duration of the event (they also had similar devices to turn off electric water heaters and pool pumps but these were far less popular). However, these didn't receive control signals over power lines - they received signals over the wireless paging network (data transmission was one-way only).

It was a very expensive program... the reference (http://www.ieso.ca/Documents/consult/sac/SAC-20160210-Item-6-PeaksaverPLUS.pdf) I found shows that it cost an average of $344 per participant, has only been used a few times and didn't really achieve its goals. They are no longer accepting new enrollments while they figure out how or if to re-jig the program. Demand in Ontario is down so much (from a combination of heavy-use industries fleeing from the province due to skyrocketing rates and conservation programs like coupons for LED lighting) that something like this won't be required again for decades. Plus, now that Ontario has smart meters, time-of-use pricing and that spare capacity, it makes little sense to clip off the peak of your revenue stream either (not that I'm cynical).

[John Lewis]

This is interesting. I looked at the linked article and see that the key feature in this technology is that their solution to the problem of signal propagation over the grid is to run the signal at the same frequency as the grid.

Data over power lines has been around for quite a while. I have two such implementations in my home: an ethernet-over-powerline extension to an observatory in my back yard (where WiFi was too unreliable) and several of my satellite TV receivers without ethernet connections talk over the powerline to the one that does. The problem with high (useful) data rates over power lines is that the signal does not survive beyond the closest transformer to your house because grid transformers do not pass signals at those frequencies.

So this company has developed a way to detect a mains-frequency signal superimposed on the mains sine wave itself. At 50 or 60 Hz, the data rate would be incredibly low (and the protocol to deal with the massive amount of noise that must be there too would lower it even more) so there would likely be no useful way to target individual devices, households or probably even relatively small areas (and a device would need to know where it was even for that to work).

At the residential level, the effect would have to be quite small and have a random effect. Imagine the power surge that would result if there was a very hot day, hundreds of thousands of central air conditioners were running, they all received the 'conserve' signal and all decide to shut off at once. Conversely, a large brownout if all the EV chargers act on the same 'OK to charge now' signal in the middle of the night. So there are still lots of challenges even after you solve the data transmission problem.

We do have (had?) a somewhat similar system here in Ontario (and maybe a few other places) called Peaksaver Plus. These systems are called 'Demand Response (DR)' systems. The idea was that you would have a special thermostat installed that could be addressed when there was a situation that required a demand reduction during a peak emergency. This was targeted to reduce air conditioning loads by increasing thermostat set points a few degrees for the duration of the event (they also had similar devices to turn off electric water heaters and pool pumps but these were far less popular). However, these didn't receive control signals over power lines - they received signals over the wireless paging network (data transmission was one-way only).

It was a very expensive program... the reference (http://www.ieso.ca/Documents/consult/sac/SAC-20160210-Item-6-PeaksaverPLUS.pdf) I found shows that it cost an average of $344 per participant, has only been used a few times and didn't really achieve its goals. They are no longer accepting new enrollments while they figure out how or if to re-jig the program. Demand in Ontario is down so much (from a combination of heavy-use industries fleeing from the province due to skyrocketing rates and conservation programs like coupons for LED lighting) that something like this won't be required again for decades. Plus, now that Ontario has smart meters, time-of-use pricing and that spare capacity, it makes little sense to clip off the peak of your revenue stream either (not that I'm cynical).

Hi Dave,

Thanks for the detailed explanation. Its very interesting. I wonder what we are upto. Another 5-10 years things might completely change how things are working now.
Thanks again, am following that company to know more.

[John Lewis]

Here is another post I came across related to Smart Grid published on Power Engineering...

While much effort is being put into energy storage as the holy grail of solutions to doom fossil fuels to irrelevance, could GDMS, coming in under the radar, be more likely to transform the global power infrastructure in the short to medium term?
GDMS is a new communications technology. It uses the frequency of the electricity network to transport data through it and can cost-effectively send and receive digital messages through electricity networks, over long distances and importantly through network transformers. It can be used to communicate with any enabled device connected to the electricity network be that a point of demand, generation or indeed storage.
“Our Grid Data Measurement System has the potential to go very far and only time will tell what the total scale of the impact of this technology will be. GDMS certainly has the potential to fundamentally transform how we manage the energy system and how to take advantage of latent flexibility within it,” says Jens Madrian -RT’s chief financial and commercial officer.
One of the most vital features of GDMS is that it can be used to remotely measure and verify the status of assets connected to electricity networks such as energy consuming assets, like freezers, and hot water tanks (demand), embedded generators or storage assets and offers the potential to generate a wealth of insightful data about how electricity is generated and consumed at the distribution network level.
Such information is essential for operators tasked with balancing electricity networks which are becoming increasingly complex with the increased variety of assets connected to them such as distributed and intermittent generators like solar along with electric vehicles and batteries. The technology can generate valuable data about the make-up of demand on the electricity system which is important to National Grid and other network operators as assumptions on the make-up of demand are used to calculate how much reserve and balancing services are needed at any given point in time.
Diarmaid Williams spoke to Jens Madrian about the potential of smart technology and the possibilities arising for the power sector. Here is the complete article http://www.powerengineeringint.com/articles/2016/10/smart-technology-a-no-brainer-for-an-optimal-power-sector.html