Tag Archives: Time of Use

DIY Time of Use Clock

Every now and then we find ourselves wondering what Time of Use period we are in. Usually this happens just as we’re getting ready to hit start on the electric clothes dryer. So I came up with an ultra simple Do it Yourself Time of Use clock. Here’s how you can make one yourself.

Taking an old wall clock, I popped off the plastic cover and made a circle out of a piece of paper that would fit inside the clock (without covering the numbers). Then I simply marked the hours along the outside edge of the paper and drew some guidelines to allow me to make the overlay. The one complication is that a wall clock is only 12 hours whereas a typical day has 24 hours (damn daylight savings time screwing stuff up twice a year!). To get around this, you simply make two sections to your overlay. In my example, I used the outer ring for AM times and the inner ring for PM times.

It’s only sort of confusing. You can see the two rings in the picture below.

Picture of a clock with colour coded sections indicating the current Time of Use period.

Quick and dirty DIY Time of Use clock. Maybe the kids will let me use markers next time.

Then I begged the kids for some markers but they said I could only use crayons so I just coloured in the appropriate sections based on the current Time of Use winter schedule. Then you just stick the overlay on top of your clock face, close it all up again, set the time and marvel at your ingenuity.

One problem I ran into was that the clock mechanism wouldn’t easily disconnect from the hands for me and I didn’t want to risk breaking the clock. To get around this, I simply cut the overlay and slipped it under the hands. A little bit of tape and it’s all good.

When the Time of Use summer season starts, I’ll just flip the overlay over, beg for crayons (or markers) again and put the summer season schedule on the other side. And that’s an Ultra simple DIY Time of Use clock to stick on the wall beside the electric clothes dryer.

Air Conditioning Hydro Usage

The hot weather started here in Eastern Ontario over the last couple weeks and up until this past weekend, it was usually quite manageable. Unfortunately on Sunday, with the humidity really high at 7am, I caved around 9am and turned on the air conditioning until about 10pm.

Thanks to the Time of Use meter we have and Hydro One’s nifty online electricity usage tool, I’m able to see how much electricity we used to keep ourselves cool(er) for the day.

Graph showing hourly electricity usage for a 24 hour period when the air conditioning is on.
Yeah, that’s a whopping 46.05 kWh used in one day. We are normally around 10-12 kWh/day. Ugh.

Now, the graph above shows the cost per hour to run the AC (and I think the dryer must have been on to cause the spike around noon) but let’s remember that these rates are not the real rates we’re paying per kWh consumed. The real rate for the 2011 Summer Season for Off-Peak is more like 12.00892¢/kWh (based on Urban High Density and before tax).

So, 46.05kWh is going to cost $5.53 (plus tax) and not the $2.72 shown by the graph. Guess we’ll be selecting our cooling days a little more diligently.

The best part of this whole deal is that it was a Sunday and thus the whole day is at the Off-Peak rate. We would have just hidden in the basement all day if it was a week day. :)

Natural Gas Standby Generator

I was recently looking at natural gas standby generators on the Costco website. Given the current electricity rates during peak Time of Use hours, I then started wondering what the cost per kWh was for a natural gas standby generator. Especially considering how low the natural gas prices have been.

So let’s do some math. Fun!

According to EnergyShop.com, natural gas is currently 25.04¢/m³ in my area. That includes all of the “add ons” that are over and above the posted natural gas rate. It excludes taxes though. As we saw before, your real electricity rate is not the same as what is “advertised” by Hydro One. We need to add in a number of extra charges to get the real rate. With the recent switch to the summer Time of Use pricing, the advertised rates increased.

Based on the current Hydro One Residential Delivery Rates, the real Time of Use prices are (based on Urban High density) 12.01¢/kWh for off-peak, 15.24¢/kWh for mid-peak and 17.18¢/kWh for peak usage. Again, these are the rates without taxes added (and minus some monthly charges that don’t translate well into a per kWh price).

So, let’s take the Generac 17 kW Standby Generator that is available on the Costco website, and figure out the cost per kWh. According to the website, it is capable of producing 16kW using natural gas and consumes 6.9m³/h at full load. So, that translates to 2.32kWh/m³ at full load. Given the current natural gas rate in my area, that means the standby generator costs 10.80¢/kWh.  WHAT?

Well, hang on, let’s not get too carried away with this. Natural gas prices are currently at all time lows.  Let’s see how much it would cost with the ~50¢/m³ that we were paying a couple years ago.  At that price, the generator costs 21.55¢/kWh to run.

Let’s not forget about the cost of the generator – $3699.99 plus around $1000 of installation/other costs (based on some rough numbers I found while Googling). To cover that, you’d have to run the “standby” generator at full load during Time of Use on-peak time for about 67142 hours all while hoping that the natural gas price doesn’t go up. Oh, and don’t forget that peak time is only for about 6 hours a day and only 5 days a week.

Oh well, that satisfied my curiosity.

Well, almost.  I poked around a bit and found a couple industrial natural gas generator sets. Unfortunately most of the large scale (2500kW – 3000kW) units I found didn’t have fuel consumption values. The $500k for a used (with no warranty) 3000kW generator set was interesting. (Yikes!)

I did manage to find the Kohler Power 400RZX which is 400kW natural gas generator. It’s capable of around 3.3kW/m³ at full load or a cost of 7.5¢/kWh. Of course, no price is listed so I’m going to assume its payoff time would be greater than the 67000+ hours of the Generac unit.

Time of Use Summer Season Starts and Rates Increase

May 1 is the start of the summer season for Time of Use electricity rates in Ontario. For 2011, this brings one good change and one bad change.

Let’s start with the good change – the off-peak rate now starts at 7PM instead of 9PM.  This is a huge deal for us as the majority of our electricity usage is after 6PM. In the winter season, that was bad because the on-peak time was from 5PM to 9PM. At least in the summer, 5PM to 7PM is mid-peak so there’s a minor reduction in electricity rate. I think the extended off-peak will help a little more in the winter season.

Chart showing Ontario electricity Time of Use periods

Now for the bad change – the rates at all levels have been increased by 0.8¢/kWh vs the rates we were paying in the 2010 winter season. So now instead of 5.1¢/kWh, we will be paying 5.9¢/kWh. That’s an increase of a whopping 15.7%. Ouch! So, even if you’ve managed to move most of your usage to the off-peak times, your bill is going up. Your base electricity usage cost is going to increase.

Wasn’t Time of Use supposed to make it possible for consumers to save money? Hydo One has updated information on their Time of Use Prices web page.

I don’t want to spoil your day so I won’t mention how much it’s going to cost to run your air conditioning this summer.  Let’s just say that you might want to look at re-mortgaging now, especially considering how much it’s going to cost to fill your car gas tank. Ugh.

So, what are your plans this summer to try and beat the heat while not breaking the bank.  I’m all ears and would love to hear your ideas!

What is Your Real Electricity Rate?

If you live in Ontario, you are usually quoted some nice low numbers as the rate you pay for electricity.  When you take those numbers and plug them into some calculations, it doesn’t seem to make much sense to bother conserving electricity because the “potential savings” are rather low in most cases.

But what is your real electricity rate?

In Ontario, there are a number of other charges that get added to your electricity bill. Some are fixed monthly charges which you can’t avoid. The ones that are “hidden” are the charges where you pay more per kWh of electricity usage. Instead of just including these in the advertised and posted rates, they are sort of hidden to the consumer and often forgotten about when people are doing rough calculations on potential savings.

Now, they aren’t completely hidden, your bill will have a nice total which sort of splits the charges out but it’s not always clear where the number comes from. Thankfully, companies like Hydro One (my electricity provider) are required to publish the numbers. What we are interested in are the Residential Delivery Rates. Here is the current (May 1, 2010) breakdown from the Hydro One page.

Detailed Breakdown of Residential Electricity Rates

– First 1,000 kWh per month (adjusted usage – ¢/kWh)
– Additional kWh
(adjusted usage – ¢/kWh)







2. Delivery:– Distribution service charge ($/month)
– Distribution volume charge (metered usage – ¢/kWh)*
– Transmission connection charge (adjusted usage – ¢/kWh)
– Transmission network charge (adjusted usage – ¢/kWh)













3. Regulatory charges: – Standard supply service administration charge ($/month)
– Rural rate protection charge (adjusted usage – ¢/kWh)
– Wholesale market service rate (adjusted usage – ¢/kWh)






Debt Retirement charge
(metered usage – ¢/kWh):


Adjustment Factor
1.078 1.085 1.092

What is missing here is a final total of what the cost is per kWh. Here, I’ll do it for you:

Total Cost:
– First 1,000 kWh per month (adjusted usage – ¢/kWh)
– Additional kWh
(adjusted usage – ¢/kWh)

WOW! Those prices suddenly seem much higher but we’re still missing one more thing – HST!  You need to add another 8% onto the price you see above.

What does this all mean?

Well, let’s look at something simple – if you can reduce electricity consumption by an average of 50W/hour every day for a year (which isn’t that difficult if you remember to turn off some of the big items like TVs, computers, etc when they aren’t in use), that would reduce your consumption by 438kWh/year.

With the regular posted rate of 6.4¢/kWh that appears to only save you $30/year. Not a whole lot. But, what are you really saving if you live in an High Density location (for example)? You are potentially saving $61/year. That’s easily a case of beer and a couple decent steaks for a pretty simple 50W/hour reduction in electricity usage.

How do I reduce my usage by 50W/hour?

Yeah, I knew I’d get you with the case of beer. Why not check out my Woods Smartstrip power bar save money post for information on a relatively easy way to do this. Other options include using CFL and LED lighting, reducing your screen time (TV and computer), or simply turning off items or lighting that isn’t needed.