Hacker News Reader

Comment by radicalbyte | Hacker News Reader

My father works in the heating world. He installed a large efficient storage water heater in the house which would basically warm the water in one go at 5am and provide it to the house all day.

What I don't understand from the article is why this is being controlled by the grid? The US is a market system, can't I buy a smart immersion heater which can then react to real time pricing information? So I warm my water up at times when the grid are paying people to use electricity?

That places the incentives correctly:

a) The entity making the investment in a new heater also gets the financial benefits thereof.

b) What's to stop your electricity supplier making your water 5% hotter every year to boost their revenues?

View on HN

The grid has topological constraints, because links in the network have finite capacity. Encoding that in a "price" would require pricing to vary not just based on total grid usage but also on the location of each load on the grid.

Tell that to grid controlled devices. You just encode a signal onto the carrier wave when you want to turn things off and on.

> can't I buy a smart immersion heater which can then react to real time pricing information?

This is exactly how Nest makes money. About 40$ per thermostat per year from the utilities.

Wow - I had no idea thats who their real customer was. Brilliant.

I’m confused, the utility companies pay Nest?

I assume thats what was meant - but these two articles are interesting:

1) getting into big data to help utils

2) shutting down (as a google does) a data service for users ---

https://www.forbes.com/sites/parmyolson/2014/01/13/nest-give...

http://fortune.com/2016/03/01/nest-shuttering-data-service-m...

---

Disclaimer: I do not know if this means they are/was/will-be providing data to utils/ users or not...

"What I don't understand from the article is why this is being controlled by the grid? "

Hypothetically if you bought your own you would need a smart meter so you're electricity company knew exactly when you had used power, there also needs to be a system to communicate to your smart appliance, to tell it to turn on. Neither of these really exist so I suppose its sensible for the utility to take ownership to iron out kinks, feel out how in works in practise and stuff.

To clarify, smart meters do exist, I don't believe they have the accuracy of metering needed for this application though.

The modern smart meters are quite accurate, much more accurate than the mechanical ones, usually to the ratepayer’s chagrin. The modern meters will pick up an induction spike from a noisy motor such as in an inefficient refrigerator or fan, where the older generation would not. How accurate does it need to be?

Its the time accuracy that matters, if its for frequency stabilisation then you need granularity in the order of seconds, rather than minutes as I believe smart meters are at the moment.

Oh no, they're way down in the milliseconds.

Electric vehicle chargers that can be controlled by the utility company exists in Norway. So in the event of electricity scarcity they can turn it off. I assume it's controlled by ripple or something, but the details are unknown to me.

In most electric markets in the US, you can’t gain access as a consumer to electricity spot pricing. Consumers and regulators value stability and predictability in power pricing.

Additionally, the system is a lot more stable if a central utility can control these water heaters as a bank of shapeable demand, rather than having each individual device making independent decisions. It’s more efficient for them to give you a periodic rebate for participating in the program and have them manage the details.

They are the only ones that can know when it's best to turn it off an on.

The utility can signal this by varying the price from minute to minute. The heater can retrieve this signal from the internet.

Most utilities won't allow data like that over the internet.

If the electricity is down, the. Internet will be down, and without this feedback mechanism working they wouldn't be able to keep the grid stable.

No, but a growing number of utilities can inform customers that it is a 'peak usage' time and customer devices can adapt accordingly.

Nest (and I assume other internet-connected) thermostats are able to accept peak-usage notifications from the power company and dynamically reduce usage. In my case (Portland Electric), it's two-way communications, if Nest can prove to the power company that I let its device reduce usage during peak-load times, I get a credit at the end of the year. The Nest in my house has almost paid for itself.

I don't know, have you seen a price graph? Part of the point of financial markets is to predict the future. Since this isn't possible to do accurately, the result is a random walk of meaninglessly precise prices when really the best prediction you can do is a wide range of uncertainty.

The point of having smart water heaters is to stabilize the market, not make it more chaotic in pursuit of more efficient trades. So instead of going with something complicated like a financial market, a simple feedback system controlled by the power company will do.

Electricity prices fluctuate on a daily basis to an extremely predictable degree.

They do now. Add a bunch of noise traders, and maybe not.

Reply on news.ycombinator.com