Energy Conservation

Last Updated 12 Sept 07
Copyright 2007 by Stephen Vermeulen

This page is a collection of information about energy conservation.


The year 2000 brought significant recent price increases in crude oil, natural gas and electricity. Some of these increases have been large enough to get people thinking of ways they can reduce energy usage to cut their bills. The classic conservation model of Reduce, Reuse and Recycle is hard to apply to energy usage as reuse and recycle are very difficult to do. Perhaps a better way to look for saving is by considering the following points:
  • life style
  • efficiency
  • alternate sources
In addition to these points there is also the issue of the (capital) cost of any proposed solution.  There are many solutions that will be found to be currently uneconomic due to their large capital cost; and hence, long payback time. Of course each time that conventional energy doubles in price some of these uneconomic solutions will become viable. Another way of view this cost variable is as implementation effort, for many people the easy things will get done, but not the hard to do things and what may be easy for one person (walking to work) may be hard for another to do.

Life Style

There are certain changes we can make to our life styles that can realize energy savings without costing money or effort. This category includes turning off unused lighting and appliances, using public transport or muscle power to get to or from work and shopping. In the future I expect that residential electrical power will be sold in a similar way that commercial power is, that is there will be a different price for the power depending on the time of day it is used, when this happens there will be direct incentive to run major appliances (like dishwashers or washing machines) in the night. Doing this now is a good idea as it helps reduce the electric peak demand, which helps the utilities defer expensive capital projects, the costs for which you will eventually pay.

The role of instant-on standby-power use in modern electronics


Using more efficient devices to do the things you want to do is generally the approach that most think about. There are many changes that can be made around the home to do things more efficiently, the main difference between these is their cost (payback time) or difficulty of implementation. For example installing fluorescent lighting can be low in cost and have a payback time of as little as 1 year, while installing a new hot water heater or furnace will be more costly and have a longer payback time.

In the modern house there are a lot of appliances that are never completely off, turns out that these could be consuming about 100W 24 hours a day in the average house.

The Woz has plans for energy efficient housing

Compact Fluorescent Lights

Fluorescent lighting has been available for a long time, it typlically requires about 20% of the power of incandescent lighting, or about 30% of the power of halogen lighting to produce the same amount of power. It has not been used much in the home environment because the standard tube based fixtures are quite ugly, special ballasted features are usually required, the lighting has a bit of an odd colour balance, and some people find it has a disturbing flicker.

In the past decade a number of designs for compact fluorescent light bulbs, which contain their own ballast and can be fitted in standard (existing) light fixtures have become available. Some of these even use special phosphers that improve the colour balance to the point that the light produced is closer to regular daylight than traditional incandescent lighting. There are typically three remaining problems with these bulbs:

In Canada Canadian Tire, London Drugs and IKEA have a good variety of solutions.  Of these IKEA has some pretty amazing prices, here are photos of some of their bulbs. There are more powerful compact fluorescent lights available, look for them at a store that sells hydroponic gardening type equipment.

Currently (Nov 2000) the cost for electricity in Calgary is CDN$0.0857/kWh (about US$0.0572/kWh). If you were to replace a single 60W incandescent bulb with a 15W fluorescent (to get the same light output) and you used this bulb on average 4 hours per day, the savings over a year would be:

365 days * 4 hours/day * (60W -15W) * 1 kW/1000W * 0.0857 $/kWh = $5.63

That's a usage rate of 1460 hours per year, which for lighting in the rooms you use most is easily reached.  This number is your direct energy savings, you also need to include the difference in replacement costs of the fluorescent bulb versus the incandescent bulb it replaces.  Incandescent bulbs cost about $1 per 1000 hours (that is most cost about a dollar and last about 1000 hours).  There are some, like globe shaped ones that cost significantly more, and there are some that look the same but are supposed to last longer (generally for a higher price though).  When I get some more prices I'll try to include an example.  The lifespan of most compact fluorescents is quoted as being 10000 hours; however, the prices of these vary a lot the most expensive being about $34 per bulb and the least being $7 per bulb.  At the expensive price the fluorescent is costing you an additional:

1460 hours/10000hours * $34 - 1460hours /1000 hours * $1 = $3.504/year

so the net savings of using the compact fluorescent is:

$5.63 - $3.50 = $2.13 per year per bulb.

However, if you can buy these bulbs for $7 each then the fluorescent actually costs less than the incandescent bulbs it replaces and hence saves you an additional:

1460hours /1000 hours * $1 - 1460 hours/10000hours * $7= $0.438/year

$0.44 per year, so the net savings of using the compact fluorescent is:

$5.63 + $0.44 = $6.07 per year per bulb.

Which means these bulbs pay for themselves in just over a year. Easy to do and with a fast payback, so well worth doing. Of course if your energy costs are higher than mine, then the incentive to make this change will also be higher.

In Aug'06 this artical claimed that WalMart is planning to push compact fluorescent bulbs hard and that the American public has actually bough very few up to now.

In Feb'07 California started looking at legislation to ban incandescent lightbulbs

LED based light bulbs

Enlux Lighting (Nov 2004) is making flood light replacement bulbs that are based on LEDs, these produce twice as much light but only use 20% of the power of conventional incandescent lights (as well as having a 200,000 hour life) so they are 10 times as efficient. This makes LED lighting about 2-3 times as efficient as flourescent lighting. Of course they are very expensive right now (about US$80 per bulb), but with the recent introduction of LED based Christmas Lights it won't be long before someone makes an LED replacement bulb for the conventional 60 or 100W light. As for why Enlux went for the flood light market first - its probably because they will be able to sell higher priced bulbs to institutional customers who can justify the higher price based on the energy savings they'll get the in future. (Nov 2004) makes LED based replacement bulbs for a number of applications, including as direct screw-in replacements for 120V incandescent lights. They currently do not have a wide range, but hopefully they will expand this in time. I have purchased three of these (the E27-W24 wide and narrow configuration in white), the narrow bulb failed fairly quickly (after about a month) and I arranged to pay the difference between it and a newly released 1Watt Luxeon. Unfortunatey the replacement bulb glowed a dim orange for a couple of seconds when I first turned it on and never worked afterwards. I returned both bulbs and they claim they were damaged by "overvoltage spikes". Given that the packaging for the second bulb was clearly marked for voltages from 90V to 230V this seems rather unlikely, as any spike that took it out over a several second period would have damaged many other devices in the house too (110V is our normal supply here). Potential buyers should also note (as of Feb 2005) that none of the bulbs are marked with a UL or CSA logo.

The LED Museum has a lot of LED related products, they even have "LED Illuminators" which are similar to some of the devices that SuperBriteLEDs sells. This is more of a do-it-yourself type shop.

Brilliance-Tech makes a number of LED light bulb modules, some of these look like those sold by SuperBrite.

B.G. Micro also has some LED array type lighting solutions

In the future quantum dots may be used to provide lighting. The are being developed by Group IV Semiconductor

Large, white-light, OLED bulbs are being developed

Seoul Semiconductor has announced LEDs capable of delivering 240 lumens at efficiencies greater than fluorescent lights

Christmas Lights

LEDs have much higher efficiencies that regular incandescent lights, now Forever Bright is making Christmas lights out of them. In Nov 2004 Canadian Tire started to advertize LED lights from Noma, they appear to be quite well made and are priced quite reasonably (about 2-3 times what a conventional strand of lights would cost, but as they are going to save you quite a bit and will last for a very long time...). Only problem is everyone wants the multi-coloured strands and Canadian Tire seems to only want to focus on the single colour strands...  One wonders if one could use the white LED strands to provide "valance" style lighting in a room?

Conventional Light Bulbs

Until now if you want to use these your only option has been to installer lower wattage bulbs. Recent research into crystaline structures has produced a new variant that may be as efficient as a flourescent bulb, the question is when can we buy one?

Other Appliances

Dish washers, washing machines, dryers, refrigerators, freezers, water heaters, furnaces, air conditioners, stoves and ovens are the biggies. The question is what potential savings are achievable and at what price.

Miele makes some pretty efficient (both in electric and water usage) dishwashers.

Brand Electronics makes a variety of digital power meters, including one you can plug appliances into to see what sort of load they actually draw.


The ARXX building system (which uses insulated concrete forms to build walls)

Could contour crafting change the house building industry buy making automated on-site construction feasible?

Windows and Doors

Alternate Sources

Using alternative sources of power or heating, such as wind or solar, is something that has been marginally economic for some time now. One could easily make a case for it in remote regions where there is a capital cost of being added to the power grid, or where for some reason fuel is very expensive, but making the economic case for adding an alternate source to a house in a city in North America is another issue. One of the main stumbling blocks is that the cost of an alternative power system is typically composed of three pieces: It may make sense now for a city dweller to install solar power as a use reduction system.  The reason for this is that in the modern home (without making significant lifestyle changes) there are a number of background loads that are consuming power at different rates nearly continually throughout the day.  If you don't believe me, just locate your electric meter and watch it spin right now.  Examples of these are small appliances like VCRs and TVs which are never really turned off (unless they are physically unplugged), home computers and large appliances like the refrigerator or freezer. If one installed a relatively small solar system, a a few hundred watts, then one could use all of its power output directly without having to spend any extra capital on battery storage. The question is would this optimal (from the use of capital perspective) solar system be cost effective?

First lets examine the yearly cost of 1W of electricity 8 hours per day:

1W * 8 hr/day * 365 days/year *  1 kW/1000W * 0.0857 $/kWh = $0.25/W-year

so the cost of a single 100W appliance would be $0.25/W-year * 100W = $25/year

This means that to roughly make economic sense the cost of the alternative enery source that produces 100W should be no more than about $250, this is because if you were to just invest that $250 at a 10% rate of return then you could use that money to pay for the power costs instead.  I did say it was rough!

So is this even in the ball park?  If you take a look at RealGoods web site, you will find that they will sell you a solar panel that has a theoretical maximum output of 100W for US$600.00 (about CDN$900.00), along with this you would still need to add a syncronizing inverter so that the power produced could be mixed in with your regular electric system, so the maximum return on the investment would be 2.7% per year (if the inverter was free). They sell a package that includes the inverter, for a 90W system this comes to about US$995.00 (CDN$1500), which makes the return on investment a maximum of 1.6%/year.  So with electricity would have to cost more than about $0.26/kWh (three times what we pay today) for annual the return on the investment to reach 5%.  This does not include the following factors:

Perhaps a more fair comparison would be to assume that the money is invested in some instrument with a guaranteed rate of return, in which case one is probably looking at a pre-tax return of about 5%, or an after tax return of about 3.5%.  If this is the case then the amount you have to invest to earn $25/year is $715.  Which is now getting into the ballpark of between $600 to $1500. In this case if your electric rates are more than about US$0.12/kWh you probably should start looking into getting some of your own generating power.

Wind Power

It looks like it might be possible to build effective wind turbines right into large buildings, see this NewScientist artical. What it looks like they are proposing is a pair of opposed airfoil shapes with the turbines between them. Now would this still be effective for residential sized structures?

Hydrogen Power

There has been a lot of hype about "hydrogen power", primarily centering about how its such a nice clean fuel. But a lot of people over look the fact that hydrogen must be produced, and the current systems of production basically end up cracking conventional hydrocarbons (like methane -- natural gas, or oil). If you produce the hydrogen this way for use in a conventional combustion based power generation system (like an electric power plant or a car or truck engine), then the laws of thermodynamics guarantee you that the end result is less efficient that just using the original natural gas or oil directly. Although you may be able to make this appear to be a cleaner system if well designed.

There are two other ways of producing the hydrogen for such a power system, one is to use a nuclear reactor of some kind to produce electricity to split water to make the hydrogen. While this is certainly feasible, one is still consuming a non-renewable and rather dangerous resource (although the fusion reactor might solve both problems, but that is always 20 years away). The other approach is to use some renewable resource (like solar, wind, wave or perhaps geo-thermal) to produce the electricity to make the hydrogen from water.

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