An action plan for saving energy on the farm - Part 1

Water heating, refrigiration, lighting, insulation - you can save many dollars in each of these areas if you do the analysis and take the proper steps

As the price of energy increases, so does the rationale for reducing energy usage on the farm. Since every farm operation has at least one residence, let's start there.

Water Heating.
Heating water is a significant energy user, regardless of fuel type. What actions can you take to reduce water-heating energy?

1. Install low-flow shower heads. The cost will be recovered within a few months in many households.
   
   
2. Reduce hot water temperature to lower standby losses. Decrease water temperature to about 120°F (49°C) -- adequate for all household uses except the dishwasher, which will top up the temperature of its hot water with an internal element.
   
   
3. Consider a water heater blanket to reduce standby losses, but only if the water heater is in a cold basement or storage room. Do be sure that the blanket will not cause overheating of the supply wires if the junction box is inside the water heater casing.
   
   
4. Reduce the volume of hot water held at higher temperatures. A 40-gallon (180-litre) water heater with higher wattage elements for fast recovery is a better option than increasing tank size to 60 or 100 gallons.
   
   
5. On-demand electrically- powered water heaters have not and will never be a viable option. They might be considered with other fuels, especially natural gas.
   
   
6. Preheating hot water with high temperature waste heat or solar collectors might be a viable alternative, depending on individual circumstances. I am using a heat exchanger on the big corn stove exhaust. It works very well and will provide payback in two years. Recovering heat from the waste-water stack is not likely to provide capital cost recovery.
   
   
7. Evaluate the water temperatures used for washing/rinsing with the automatic clothes washer. Cold-water soaps are being promoted as energy savers.
   
   
8. For those of you with milking operations, consider using milk heat transferred to water. But it must be evaluated on an individual case basis.
   
   
9. And, last but not least, keep an eye out for leaking taps and valves and repair or replace them immediately.

Refrigeration.

The next major user of energy in the residence is refrigeration - namely the freezer and the refrigerator. Many of us like to boast that the old freezer or fridge has been operating trouble-free for many years.

We acquired a brand new 20-cubic-foot chest freezer in 1967. In 2003, I started an electrical energy use monitoring project to prove to my wife that the old freezer had to depart.

The old freezer was using over 1,800 kWh per year. At 10 cents per kWh, the operating cost would be over $180 per year. The new upright, slightly smaller, "Energy Star" freezer has an Energuide rating of 409 kWh per year. The freezers were exchanged in October, 2005. The payback in energy saved at 10 cents per kWh is $140 per year. The new freezer will have saved its cost in less than five years.

Lighting.
In warm locations, replace incandescent bulbs that are regularly used with fluorescent lights. The new spiral fluorescent bulbs permit substitution in almost every light fixture. In one stairway, I switched from 180 watts of incandescent bulbs to only 40 watts of the spiral fluorescents. I now do not feel nearly as guilty leaving those lights on, both for convenience and security. At 78 per cent, the reduction in wattage and energy usage is significant.

I just replaced the 22-watt circular fluorescent kit in the floor lamp that is on a timer for security lighting after at least 10 years of duty. It provides the same light output as a 100-watt incandescent bulb and an acceptable colour as it is warm white. It saves 78 watts each hour it operates. That provides an energy saving of one kWh for every 12.8 hours of operation. For an average on-time of 6.4 hours every day, the annual energy savings will be over 180 kWhs or $18 dollars per year. The fluorescent unit cost ten dollars and change. How can I go wrong when the unit life is 10,000 hours or seven years?

But, remember, fluorescent bulbs/tubes are not for every location. They perform best at ambient temperatures over 70°F (20°C). For lower temperature locations, they can be considered but will require more expensive cold-start ballasts and special enclosures to maintain optimum ambient temperatures around the tubes.

For "welcoming lighting" to greet visitors, consider motion sensors to turn lights on and off. They are cheap and easy to install. For security lighting of the dusk-to-dawn type, consider the high-pressure sodium (HPS) light fixtures. They are much more energy efficient than the mercury vapour units we used - and many of these are still in operation. The 70-watt HPS fixture will provide about the same amount of light as a 175-watt mercury vapour unit. The HPS bulbs are expensive ($20-plus) but do have a relatively long life. I just replaced one after almost eight years of overnight service, 365 days of each year.

Other short-term/low cost energy savers.
Interval timers that can be set for up to 30 minutes can be installed in lieu of a switch for bathroom fans. The fan is a good idea to remove odours and moisture, but if left on it is a great energy waster. Another solution is to wire the fan through the light switch. When the light is turned off, the fan will be also, but the fan can be on or off by choice when the light is on.

Recently I have also seen motion-sensitive light switches in bathrooms. After a preset period, if there is no motion in the room the light will be switched off.

Another item of note is for older water pressure systems. If your system does not have a pressure tank with a baffle or bladder, the air in the tank will eventually be absorbed into the water. In other words, the pressure system will become "waterlogged." When that happens, the pump will start and stop frequently each time a tap is turned on for a glass of water.

Once or twice a year, regular recharging of the system with air or a new style - possibly larger - storage tank should be considered. Pump motors have high power usage at startup and frequent starts are likely to shorten the life of the water pump motor.

Some longer-term issues.
Houses can be tightened up to prevent excessive air exchange caused primarily by wind pressure in rural areas. This process requires weather-stripping, caulking and possibly new windows, as well as the addition of insulation where practical.

This draft-stopping process must be given a high priority, regardless of the type of heating system.
But one word of caution. If you have a fuel burning unit of any type, do make sure that combustion air is readily available. Houses can be sealed too well. If necessary an air inlet to the furnace room or an air-to-air heat exchanger will provide the necessary air exchange for moisture control and combustion air.

The ultimate choice.
With the present costs of all fuels and the prospects for future price increases, a longer-term action plan should be considered.

If you are building a new house or upgrading a heating system and want air conditioning, you should be evaluating the payback potential of a ground-source heat pump. Remember that heat pumps provide many times the heat equivalent of the electrical energy used. The multiple is called the coefficient of performance (COP).

Heat pumps just move heat. They do not create it. A well-designed system can provide both air conditioning and hot water in addition to space heating. BF

Agricultural engineer Ralph Winfield farms at Belmont in Elgin County.