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Ontario Air Conditioning Bills Generating Heat

Last updated 2008.07.25

Well, if you ended up at this page, odds are you have received your electrical bill for the summer, and while your air conditioner kept you cool then, the price for that electricity has got you hot under the collar now. You're the folks the utility folks worry about in the peak of summer, and think of fondly come billing time.

If you are looking for someone to rant at, try your relevant politicians. They're used to it, and they paid for it. Who knows, it might even help in the short term. It worked on the Ontario government in 2004.

If you are looking for someone to blame, try looking in the mirror. You got a serious warning in August 2003 (you do remember the blackout, don't you?) You got off cheap last summer (2004), because it was unusually cool. The summer of 2005 featured high temperatures that pushed the grid to the max, and exceeding the province's ability to produce electricity on a regular basis.

If you are looking for a way to avoid high air conditioning bills in the future, the secret is energy conservation, specifically the electricity used to run your A/C. Read on.

Do The Math

Let's consider a "typical" Ontario household. It uses about 25 kWh per day (or more) on a regular day. In a thirty-day month, that comes to 750 kWh, the limit for the lower residential rate. For electricity consumed up to 750 kWh per month, the rate is 4.7 cents per kWh, and 5.5 cents for power consumed beyond that amount (subject to change). Of course, this is just the "generation" price. What you actually pay is considerably more than that; about double to triple that amount. So, let's say you pay 12 cents per kWh in reality (including the "generation" charge, the distribution charge, regulatory charges, debt retirement charges and taxes), then that 750 kWh really costs you $90.00 for the month.

Now, let's see what happens when it gets hot and humid and that central air conditioner fires up. Let's assume you have a relatively small unit, consuming just 4,000 watts (that's a unit rated at 17 amps and 230 volts), and it runs seven hours a day (probably more during really hot weather). Well, that's 28 kWh per day. That's more electrical power being consumed by your air conditioner than everything else in your house combined! But, it gets worse. Because you are beyond the 750 kWh threshold, this electricity is costing you not just 12 cents per kWh; this extra consumption costs 14 cents per kWh. So your daily cost jumps from $3.00 to $7.00. That's $210 for the month instead of the usual $90. But, you aren't finished paying yet. This extra juice that is being purchased from outside the province at peak demand times costs more than the province is charging under the "generation" fee, so the difference will eventually find it's way onto your provincial income tax bill, or future electrical bills. For that tab, the provincial total is well beyond a billion dollars ($1,000,000,000.00) – and still growing.

Interested in reducing your household air conditioning bill yet? Here's the four-point plan for personal energy conservation. 1. Keep the heat out. 2. Make it cool inside. 3. Reduce indoor heat production. 4. Cool the people, not the building.

Keep the Heat Out

Invest in good insulation and weather sealing. It will help keep the heat in during the winter, and the cool in during the summer. Storm doors and windows will help reduce air leakage, and provide an additional barrier against heat being conducted into your structure. When it comes to energy conservation, this is the first, best step you can take.

Reduce solar gain. The sun is a potent heat source, especially in the summer. The trick is to prevent it from shining on your house. Think of it as sun-block for your home. While curtains and blinds on the inside of windows produce a small energy conservation benefit, there is a much bigger gain from shading the windows from the sun completely. Awnings, shutters, outdoor blinds and shade cloth are all good options. Sun that doesn't reach the window can't heat up your house. Sun that doesn't reach the exterior walls can't heat up your house.

When it's hot outside, and cool inside, close things up to keep the heat out.

Make it Cool Inside

When it is cool outside, e.g., at night, open up the windows and let the hot air out and the cool air in. This will take some time, as it is not just the air you are trying to cool, but the actual building structure (walls, floors) and contents (furniture). Use fans to move more air to speed up the process; Mother Nature doesn't always provide a breeze to help out.

If you are going to be running cold water anyway (say for washing vegetables or taking a bath or shower to cool down), collect that water (using a bowl or bucket or drain plug). As that cold water warms up to room temperature, it is extracting heat from the room. Once the water has reached room temperature, you can use it to water plants, wash the car or whatever to get additional use from it instead of just dumping it down the drain.

Try adjusting to a slightly higher temperature in your home. If you are accustomed to keeping the thermostat at 24 or 25 degrees Celsius, try going a degree higher and see if that is acceptable to you. It means your air conditioner will work less. In our house, we go to 26 during the day. After 10 p.m., we try to drop the temperature in the bedrooms to 22 for sleeping, when power demand is reduced (most industries and commercial establishments have closed). Some nights we can cool down by opening windows and ventilating with cooler outside air, but some nights it just doesn't cool down enough for that to work, especially in our cities. If we can get the house down to 22 or lower, and close up in the morning, most days the air conditioning doesn't come on during the day (even when outdoor temperatures reach the low to mid-thirties). This approach should really pay off when smart meters come into use. You're going to pay for them; why not try to benefit from them and the three-tier pricing that comes with them. (Here's the proposed three-tier pricing schedule in picture form.)

Use air conditioning if you have it and when you need it. However, the tips on this page should help reduce the amount you need to use it, conserving energy, and how much it will cost you.

Reduce Indoor Heat Production

If the air conditioner is running, you should try to avoid using your heating appliances in the kitchen (stove, oven, indoor grill, toaster, etc). If you really have to heat something up, try to use the microwave, or go outside and use the barbecue. If you want to try something really cool in the cooking department, look into solar cookers. When it comes to energy conservation, it's simply counter-productive to use energy to produce heat which will then require more energy to counteract.

Don't use the refrigerator or freezer as a cooling source. They produce more heat in your house than they do cold inside the unit.

Conserve your personal energy, too. Try to avoid heavy physical exertion on really hot days, even in your air-conditioned house. Your effort produces heat. Time your labour to take advantage of the relatively cooler parts of the day – early morning and late evening, and do as much as possible outdoors.

Turn off appliances that are not in use, including computers, televisions, radios, stereos, etc. They all produce heat when in use. Some even produce heat when the are "off", e.g., "instant-on" televisions consume 5 watts or more continuously when turned off. Put such devices (e.g. some fax machines, computer monitors) on power bars with switches and turn off the power at the power bar. It's an energy conservation double-win; less energy consumed and less heat to overcome.

Replace your high usage incandescent lights with fluorescent fixtures or compact fluorescent lights (screw right into the existing socket). Fluorescent lighting uses less than 25% of the energy of incandescents for the same lighting (lumens), and produce less than 20% of the waste heat. Why heat your house with your lights when it is already hot? Compact fluorescents cost more than traditional incandescent bulbs, but will more than pay for themselves with the electricity they will save over their life.

Use cold water for your laundry instead of hot.

Hang your clothes to dry instead of using a clothes dryer to cook them dry.

Put additional insulation (jacket) around your hot water tank and the hot water pipes. Use the energy you pay for to heat the water, not your house.

Cool the People, Not the Building

Dress for the temperature. When it's hot inside, wear short pants, short sleeve (or sleeveless) shirts and sandals. When going into the hot outdoors, wear lightweight, light-coloured, breathable, loose fitting clothing.

Use fans (ceiling fans, box fans, floor fans) to move the air in the room. As the air moves over you, it removes the air closest to you which has been warmed by your body, and replaces it with slightly cooler air. Fans use a lot less power than air conditioners.

Do you have a habitable basement? If so, you're sitting on a cold mine. It is almost always cooler there due to the effect of the ground surrounding it which does not vary in temperature much (below the frost line) over the course of the year. Consider bunking out in the basement if it will help you sleep.

Target the parts of the house you want to cool most. For most people, this is the bedrooms, especially as you are trying to get to sleep. This can be done using room (window or floor units) air conditioners, or by adjusting the air registers in the various rooms in the house – more cool air to the bedroom(s) and less to the other rooms. Why pay to cool rooms you are not using?

Take a cold shower or bath. This will help cool you down. On really hot evenings, this can cool you down long enough to get to sleep. Even water at room temperature is colder than you are, so it will help cool you down.

Keep cold drinks in the refrigerator, even if it is just a pitcher of tap water. Stay hydrated. Perspiration is nature's way of helping keep you cooler.

The efficiency of air conditioners has improved over the past few years. If you need to replace your existing unit, look at the energy usage ratings (e.g. Energy Star) and use that information to guide you in your purchase decision. Your air conditioner will likely cost you more in electricity in its lifetime than the original purchase price.

Well, there are a few tips on low-tech, low-investment ways to help reduce your air conditioner use, and the associated electrical bill. You may have heard that the government of Ontario wants to create an energy conservation culture. These tips will help you get there. For other energy saving tips and more aggressive cooling techniques, look at some other areas on our website.

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