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Comment by kolya3 | Hacker News Reader

Honest question, is this solving a problem and who has this problem? I pay about $30/month for electricity and I already know it goes up to about $80/month during the winter months. $200 seems like a lot of money to pay for someone to tell me what I already know.

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Wattvision tends to cut your power use, because you're probably wasting power in ways you don't know about. When you first install it, your initial reaction is generally "why are we using so much power?" Then you walk around turning things on and off and watching what happens to the graph. You usually discover some surprises in the process, and those change your behavior.

You make what you measure. Watch any number carefully enough and you'll tend to optimize it, and most households have significant room to.

I can understand the first usage being kind of interesting and enlightening, but I'm not sure if its $200 kind of interesting.

It seems like this would be of more interest for commercial applications.

How about a device that actually directly saves you power?

Well that's what my friend's startup focuses on currently piloted in South Africa. The startup built a device that reliably saves power. You don't need to pay any fee up front for the device, you "pay as you go" on amount of saving made on monthly basis. No catch. Average savings currently are around 10-15%, engineering team is pushing the numbers up as we speak. Business has gotten necessary funding and even the primary energy supplier has come on board to put an initiative together that would implement the solution to all street lights in the country in the near future. South Africa is currently going through energy crisis due to huge demand and lack of supply.

PS. My wife is one of the co-founders. :)

How does it work?

What is the average time to recoup the cost of the meter and start actually saving money?

If you believe the normal claim that you will save 10-30% and your average monthly power bill is > the cost of monitoring it will take you less than 1 year to pay itself off.

So if your bill is $150 a month, this system (or similar) should pay for itself within a year - IF you try to save power using it.

Saving energy doesn't only have to be about money.

I've always thought that light switches & sockets should have meters on them.

http://www.42u.com/images/power-tower-xl-ptxlv016.jpg

Lots of datacenter grade stuff does. It's really convenient.

Oops, I was about to upvote, but I hit the wrong arrow. And there's no undo. Sorry!

Until recently it was very difficult to get the data from the sensors to a useful place. Wireless networks and common always on internet connections have changed that.

What are the chances some sort of clever metering will be built in to new, higher end houses?

I wouldn't bet on it too soon. When I was involved in the home automation industry back in the mid/late 90's it seemed like that sort of thing was imminent.

Invensys and CutlerHammer both had power-monitoring devices, electric meters and so on (I still have some CH power monitoring sensors on the main power lines at my house with a system that I put together that tracks KwH, heating oil consumption and a few other metrics).

Anyway... I haven't really seen those products move an inch in the last dozen years (other than press releases).

While I do believe that the real-time feedback is helpful, I also more strongly believe that people who really want to cut their power usage will do so by simply turning more things off or using things less. For the most part, a monthly feedback cycle isn't really THAT long. In some cases the month-long feedback loop let's you measure a more cumulative effect in dollars instead of cents.

I also think that automation has been imminent for long enough to be suspect.

But people responding to feedback is not something to just dismiss. Monthly isn't the same as on demand which isn't the same as "out in the open." If sockets changed colour from blue to red as the burned electricity, consumption would go down.

Measuring power at the meter is nice, but I'm wanting to measure the power per circuit in the house. Given how small electronics have gotten, I've been wondering if it's possible to put a simple monitor in a circuit breaker. It would make it easier to narrow down the power hungry devices in the home.

I know it differs from the whole internet-connected/constant monitoring solution, but there is a device that you can use to do this manually called the Kill A Watt: http://www.p3international.com/products/special/P4400/P4400-...

Installed cost for these home automation solutions quickly tends to exceed $1000 making them impractical as a cost saver. The sensor costs are suddenly dropping as competition heats up.

Hopefully innovative, web enabled solutions from fast moving startups re-invigorate this sector. I'd sure love to.

Extremely likely. There are good chances that in 30 years most houses are as automated as our off-grid house on Great Barrier Island and come with power monitoring as standard.

http://blog.gridspy.co.nz/2009/08/the-barrier-house.html

We plan to provide the devices today.

Yes, extremely likely. Hey gridspy guys, do you want to see if we can find some common ground between wv and gridspy? :) ping info@wattvision.com

It seems to me that live monitoring is most useful to people who look at the power bill and wonder "where did that all go?" The biggest people asking this question would be large power users such as businesses.

Businesses spend more money on power and need more detail to really drill into their power usage. That is why Gridspy (my startup) is focusing on them first.

http://gridspy.co.nz/

Because of this, I think that Watt vision and Gridspy are in slightly different markets, perhaps even complimentary.

The consumers interested in our system typically live in big homes in the suburbs and run their AC or heating quite a bit. That's not to say we can't also help landlords and small business owners who are also interested in saving money on their energy expenses.

We spend $150-$200/mo. We're a small house in Chicago with 4 occupants. For any likely % of efficiency we'd gain by measuring electricity use in our house easily, it's trivial to work out the small number of months it would take for this to pay for itself.

There's also a big difference between knowing in the abstract that (say) water kettles are expensive, and knowing specifically what is costing us money in our house.

"you can't improve upon something until you can measure it" -- Albert Einstein

But what scale of measuring is necessary? Do I need to know what devices drain what power when it's simple to assume that electric heaters consume a vast amount of energy during winter and that air conditioners consume a vast amount of energy during the summer.

I believe the OP was asking is what is the benefit of this additional measuring and monitoring. What will it provide beyond the KW/h information I can get from my own meter?

But how much energy? Do you know how many $$ of your power bill are down to AC and how many are due to hot water? If you turn down your AC one degree, can you tell at the end of the month how much you saved?

It is hard to isolate particular elements of your house's usage without either a lot of legwork or a decent sensor solution. Knowing how you use your power lets you make smart compromises and invest in power saving measures such as better lights, solar hot water heating, insulation or smarter appliances.

It is especially important if there are many people living or working in the same building, making it hard for any one person to get an accurate picture in their minds of the power consumption.

I know exactly how much electricity my devices use, and I certainly don't need a meter to figure out how or what they use. I worked as an electrician, I can work out the power consumption of every device, so yes personally I know where virtually every penny of my money is going.

I also have an induction meter (IIRC accurate to ~10W, I've used ones accurate to ~1W) that cost ~$60, so I seriously don't see the value in a $200 system that can't do much more than me, a pencil and time.

I see the system as a bit dishonest when you can tell people to look at a plug and read the amperage draw and tell them to times by 110. It's especially dishonest when the majority of devices now tell the wattage due to EnergyStar requirements.

I agree that eyeballs + a calculator can go a long way. However, the amperage draw on the back of your power supply or device is typically worst-case (maximum) current, not average current. Similarly, EnergyStar numbers do a little better, but everyone's usage pattern is different. For instance, what is the wattage consumed by your computer? It is certainly not the summed TDP of all components in the box. It is also not the rated wattage of your power supply. For things like this that are not "dumb loads", you need a more sophisticated way of measuring power consumption.

Personally, I'm with you in preferring a different solution. I use a Kill-a-Watt (http://www.p3international.com/products/special/P4400/P4400-... ) to measure actual average power consumption over a few days for each major device in my home. Seems to work fairly well.

That's like a race-driver saying that ABS brakes are inefficient because he can brake better than the computer (true, but 90% of the rest of the population can't).

Or an amateur-chef scoffing at someone going to a steakhouse to get a good steak, because he knows how to make them good at home, much cheaper.

Or, say, a geek saying that graphical UIs are bad because he can work much faster on the command line and in vi.

I have two electrical heating devices, but both have a thermostat. I can read the label and do the math and tell you exactly what they cost to have running. But I can't tell you how often the thermostat turns them on and off, and I'm not going to spend a day with a stopwatch, looking at the light going on and off. I can't tell how the temperature outside might affect my heating usage. I can't tell how two persons showering affects the floor-heating in the bathroom, over one or none.

A logger like the one Wattvision offers could offer some input to that.

Many many people will pay $200 dollars for the time component in your example.

You cannot read your meter as you walk around the house switching appliances.

Many (if not most) home-owners are far less aware of the power usage of common appliances than we are. They probably don't even know what a kWh is.

I think it could be handy for businesses, universities, research labs, or anyone else that has a big power bill. Getting it itemized would be interesting.

That is exactly what we do. http://gridspy.co.nz/

And doubly so for businesses with high power needs, such as data-centers or even software houses.

But this doesn't seem to be their target market. The simplicity of installation, and the website, point to home users. If you're running a data center you probably already have more sophisticated systems in place.

Good feedback. Yeah we can do that, too. ;)

It would be more interesting to have a sensor on the electric meter, then a few other units that you can put between appliances and the wall outlets so you can measure specific devices and tweak usage based on that data.

I have electric heating, last winter my average bill was $400 however my first bill was $490 little changes like leaving some doors closed during the day, and others open had $50 differences. I definitely would pay for that data, the savings would pay for it.

Electric heat is like converting steak (high grade electric power) in to hamburger (low grade radiated heat). It is probably the least efficient way you could possibly choose to heat a house.

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