03131 Energy issues in the kitchen

With its array of gadgets and machines, all powered by energies that are destructive of land or air or water, and connected to work, market, school, recreation, etc., by gasoline engines, the modern home is a veritable factory of waste and destruction. It is the mainstay of the economy of money. But within the economies of energy and nature, it is a catastrophe. It takes in the world's goods and converts them into garbage, sewage, and noxious fumes—for none of which have we found a use. — Wendell Berry

The kitchen is an area of intense energy and resource use. Understanding the energy flows and sinks of your kitchen is critical to successful permaculture design.

Waste Heat. As we use energy, it loses some heat (thanks to the 2nd law of thermodynamics). We refer to this as “waste heat.” Heat always moves toward cold, which is why we think of hot items “radiating heat” as they cool down.

POP QUIZ! How many times thus far has the 2nd law of thermodynamics been mentioned in iPermie? What does the frequency of references to this scientific principle suggest about its importance for permaculture design and sustainable living?

We like waste heat from cooking in the winter, when it is cold. It is not popular in the summer, when it is hot.

In both summer and winter, waste heat is expensive energy that entropy drains into a sink. In this case, the sink where the energy dissipates is the atmosphere surrounding the hot pot or stove or oven. Or it may actually be your kitchen sink, as a hot liquid drains down into the sewer system.

There’s not much you can do in summer about waste heat, except to move heat-producing activities like cooking outside. This strategy deflects the unwanted waste heat from your living quarters.

But in the winter, you want that heat. So you look for ways to recover and collect that heat in your living areas. You won’t get all of it thanks to the laws of thermodynamics, but each new use helps.

This can be as simple as letting hot water or liquids cool before pouring them down the drain (winter strategy). Others are more complex, like air to air heat exchangers used in ventilation systems.

Calculating kitchen energy consumption. If you use natural gas or propane for cooking only, calculating your energy consumption for cooking and hot water could be a simple matter of looking at your summer natural gas bill or adding up the bottles of propane.

If you use natural gas or propane for heating water and space heating, you will have to do some math and time your cooking.

Suppose you want to know how much natural gas it takes to boil a chicken. To measure this, you could time the cooking. The formula is —

TIME of cooking in hours TIMES the BTUs PER HOUR of the burner EQUALS BTUs of natural gas used to cook the chicken.

To convert these BTUs to cubic feet of natural gas (a common billing unit), DIVIDE the BTUs by 1020, which is the number of BTUs in one cubic foot of natural gas.

Compare different types of cooking to determine the energy conservative fuel efficient method. For example, it could take as much as two hours to roast a chicken in the oven. It would take about an hour to poach a chicken in water on top of the stove. It would only take 15 minutes to cook a 2-1/2 lb chicken in a pressure cooker. Which method uses the least energy?

Or consider a pot roast. Cook it in the oven for about 3 hours, or cook it in a pressure cooker for 45 minutes or cook it in a crock pot for about 8 hours.

This suggests a design decision for anyone who wants to cook chicken or beef roast: Add a pressure cooker and crockpot to your kitchen equipment if you don’t already have them.

Here’s a chart of pressure cooker times.

http://fastcooking.ca/pressure_cookers/cooking_times_pressure_cooker.php

For 120 volt appliances, the best way to determine usage is with a Kill-a-Watt meter or similar device and actually measure the consumption. Do this over time and you will develop detailed statistics on how much energy these appliances use.

A 220 volt kitchen appliances (like stoves and ovens), rated at 2500 watts, that runs for one hour, uses 2.5 kwh. However, unlike a stove-top burner, an electric oven does not run continuously. It cycles on and off to maintain the set temperature. One rule of thumb I found while researching this chapter suggested dividing the amount that would be used if run continuously for an hour by two. Other than that, I am not aware of a low-tech practical way to determine the exact energy usage of an oven. Convection ovens do use less energy than regular ovens.

We have a similar problem calculating the natural gas or propane usage of an oven in operation.

Any way you look at this though, in the kitchen you need to design for reduced energy consumption.

Demand destruction. Developing a kitchen that will care for people, care for the planet, and have a care for the future means using less energy. Look for opportunities to completely reduce or even eliminate the use of fossil energy, in favor of renewable/passive solar or manual alternatives.

How can I do this with less fossil energy?

How can I do this without any fossil energy?

Scrutinize every appliance you have and ask yourself if its energy consumption is worth it. And after observing and evaluating, you may decide that yes, this energy expenditure is valid because it leads to other synergies later or it is work that you need or want to do.

That’s why a pressure cooker is useful. It does the same work as a boiling pot, only much faster.

Later in this article there is a list of little tricks you can use in the kitchen to shave your demand, a few BTUs at a time. Don’t scorn such pennies or euro cents. Pennies add up to dollars and cents add up to euros and every BTU you don’t import from the coal mines and etc. is a BTU you don’t have to pay for and a BTU that doesn’t damage the earth. The popular attitude that “it’s not worth it” to save “in small things” is one of the more toxic aspects of the currently popular madnesses and delusions of crowds. Here’s a useful wisdom saying — “The one who is faithful in small things will be faithful in large things.”

Use your crockpot. It is one of the most conservative of cooking appliances. Maybe you could add a retained heat cooker? This is an insulated box that cooks via the retained heat of the food placed inside a box. Bring a covered pot to a boil, then place it inside of the retained heat cooker. The insulation retains the heat as the food continues to cook.

Appropriate Scale. Appropriate scale keeps visiting us everywhere we go in the permacultured kitchen. Use kitchen appliances in proportion to the size of what you cook. If you need to boil a small amount of water, use a small pot and a small burner. Most people don’t need a supremo-gigantico-maximo-humongoid refrigerator with four different spouts or chutes puncturing its door plus a hair dryer, drink mixer, and automatic defrost. It’s taller than you are. Of course, people may think they need something that huge. That is a delusion fostered by clever advertising propaganda that sells extra large appliances to make extra large profits for the appliance companies.

When it comes to appropriate scale, the question "should we substitute energy for time," often comes up. Is it really worth it to run the food processor to chop one onion for dinner, when you add in the time required to get the food processor, set it up, do the chopping, clean it afterwards, and then put it back where it belongs? If you’re doing just one onion, probably not. If you need to shred 20 pounds of carrots for a large food processing or cooking project, the expenditure of time and energy may be worth it due to the time savings it offers to the people in the kitchen.

If you bake one pie, a tabletop convection oven will be a better choice than a full-size oven.

Do only what is needed. If you need a cup of boiling water, don’t boil a quart. Prepare what you need and don’t waste energy boiling water you don’t need. You may not need to cook every meal. As you develop your menu plans, look for opportunities to prepare meals that don’t require cooking. This may be a seasonal strategy, because just as everything else, your permacultured kitchen changes with the seasons.

Induction Cook Tops. If you use electricity for cooking, induction cook tops are generally considered more efficient and energy conservative than a regular electric kitchen range. With this form of cooking, heat is applied only to the cooking vessel. No extra energy goes elsewhere. However, it only works with cooking pots that are made of magnetic materials, such as cast iron and stainless steel. More information about induction cook tops is available at http://theinductionsite.com/proandcon.shtml.

Solar cooking. Free heat from the sun can make a significant contribution to your kitchen energy budget. Free BTUs float down on the beneficial rays of our friendly neighborhood star every time the sun shines. I built a solar oven out of a cardboard box and aluminum foil and measured 325 degrees inside on a spring afternoon. I’ve seen a “Global Sun Oven” at work (a manufactured version solar oven) and it works as advertised.

The pre-eminent internet site about solar cooking is http://solarcooking.org/. See http://www.solarcooking.org/plans/ for a directory of plans (and photographs of the cookers.)

The Global Sun Oven is a commercially manufactured household solar cooker. They make a village size version that could be used commercially in the US. Access their information at http://www.sunoven.com/ .

Retained Heat Cooking. This is a crockpot without electricity. You heat the food to boiling, cook it for 5 to 15 minutes depending on the food (5 minutes for rice, 15 minutes for large dried beans or whole potatoes) and put it in an insulated box. According to the folks at the solar cooking archive, it can save 20-60% of the energy required to cook a food.

The Solar Cooking archive has great information about retained heat cooking at http://solarcooking.wikia.com/wiki/Heat-retention_cooking .

E-book on retained heat cooking, $6.99 from Bamboo Grove Press, http://www.bamboogrovepress.com/Ebooks.htm. I have a copy and it is worth it if you plan to incorporate retained heat cooking into your design. The history of the hot box has a fascinating history and it is a good example of how the cross-generation transfer of domestic knowledge has become problematic over time. The author created her first hot pot using a laundry basket. She simply wrapped a cast-iron Dutch oven with several layers of blankets and sleeping bags and put it in the basket! She said it took about 5 minutes.

Fuel Efficient Outdoor Stoves. The “Rocket Stove” is an efficient way to cook with wood. The Solar Cooking Archive has a page on these stoves at http://solarcooking.wikia.com/wiki/rocket_stove. Approvecho has what is probably the definitive site on rocket stoves, including extensive plans, at http://www.rocketstove.org/.

Ice Box. An even more low-energy option for refrigeration than my chest refrigerator is the old-fashioned ice box, using ice made in your freezer. Here is a plan to build a modern version of an old-fashioned ice box: http://www.ehow.com/how_5020653_make-ice-box-refrigerator.html.

Outdoor Bread Oven. In 2004, I visited Italy and stayed for part of the time with a farm family in a small village. They had an outside oven — a “forno” — which they used to bake bread and other items. The Additional Resources folder has references to books on this subject.

Quantity cooking. If you plan to cook one item, for less than twice the energy, you can cook two or three or four. Cook, freeze, and serve later is an excellent strategy for reducing energy consumption in the kitchen.

Food Preservation. Use solar food dryers to dry food. One simple design is a couple of racks covered with mosquito netting, hung in the sun. A more elaborate version can be built that draws air in, heats it, and exhausts it through the top. This type can dry several racks of food. Once again, the Solar Cooking Archives brings us a rich trove of information on the subject. http://solarcooking.wikia.com/wiki/Solar_food_dryers . I have often thought that once the petroleum gets too expensive for our cars, we’ll park them in the sun and use them to dry food. In fact, we could do that right now.

Cooking Outside. Cooking inside during the summer adds heat and humidity that you don’t want. If you have air conditioning, it will take energy to get rid of the cooking heat and humidity. Thanks to the laws of thermodynamics, it will take more energy to cool and dehumidify the air than you put into it while cooking. If you spend 2,000 watts cooking, it will take more than 2,000 watts of cooling energy to remove the heat and humidity from the air. If you don’t have AC, cooking inside during the summer will make the inside of your house or apartment more miserable.

We cook outside all summer long, presently on the front porch, which is cool and shady. I use a crockpot, a natural gas stove that we had converted to run on propane, a “turkey fryer” (when we do canning), and a pressure cooker. Before we got the propane kitchen stove, we used a two-burner propane camp stove equipped with an adaptor so it will run off a 20 lb. cylinder instead of the expensive 1 lb. cylinders. These are available from propane dealers “everywhere.” I use about two-three twenty-pound cylinders of propane for four months cooking on the porch, 15 — 15 gallons. I do my prep work in the kitchen and take the food out on the porch to cook.

Gas versus electric stoves. Gas and electric cooking methods have similar efficiencies in the kitchen. Natural gas and propane release pollution to your interior environment — nitrous oxide, carbon monoxide, and sulfur dioxide. Electric stoves using grid generated electricity from fossil fuel resources release pollution into the atmosphere. One way to finesse this is to buy wind generated electricity from your local utility.

How will you cook if you can’t get grid-generated electricity or natural gas or bottled propane? The time to learn to cook without hydrocarbons is before the power goes out and the natural gas pipelines dry up.

Hand dish washing in the sink versus electric dish washer. Hand washing of dishes is more energy conservative than using a dish washer. Sure, there’s studies that say this isn’t true. I wonder about the involvement of dish washer manufacturing corporations with those studies and in any event, I’ve measured our usage of water when washing dishes and hand dish washing is certainly more water frugal than using a dish washer. Not buying a dish washer avoids the energy investment in the machine.

If you have an automatic dish washer, don’t use it. If you don’t have one, don’t buy one. If you have one and you just have to use it . . . Resist the temptation! If you fail and give into temptation, at least don’t use the heating element to dry the dishes. Let them air dry. See this Dept. of Energy page on dishwashers. http://www1.eere.energy.gov/consumer/tips/dishwashers.html for more information on greening our dish washers and their environmental/energy impacts.

The embodied energy of the appliance counts against the automatic dishwasher as an energy debit. I have lived all of my life since leaving home without a dishwasher. I always just wash the dishes. Despite my busy lifestyle, and cooking as much as I do, I don’t find this to be a terrible chore. I don’t think that washing dishes is beneath my dignity as a human person. I like to eat. How can I disapprove of washing the tools of my eating?

Ignore the pro-dishwasher propaganda that purports to “prove” that washing dishes in a dish washer is as energy and water efficient as doing them by hand. As we should all understand by now, there are lies, damn lies, and then there are statistics and research studies paid for by corporations looking for profits. The pro-dishwasher propaganda fails the common sense test.

Tips for hand dishwashing.

• Do a good job of wiping and scraping the plates into your compost container.
• Put a couple of inches of hot water in the sink with the dish soap and while the water fills the sink, wash any small, relatively clean items like glasses, cups, and silverware. Rinse them with water running into the same sink, thus double using the water — once to rinse and then to wash. Continue this until the washing sink is as full of water as you need it to be.
• Start running cold water in the 2nd sink or a basin (a basin is better if you aren’t plumbed for grey water). Continue to wash and rinse until the rinse sink is as full as it needs to be. Then, dip the rest of the items after you wash them in the rinse water and wipe dry with a towel. Water plants with the water.
• Do the dishes promptly. Letting food dry on the dishes increases the work. Leaving dirty dishes “for later” creates a large pile of dirty dishes that will take too long to wash. That's what you'll think anyway. “They say” that a sink full of dirty dishes is a leading cause of eating out and I believe that. Wet dirty dishes are a major food safety hazard. Wash them after each meal, avoid aggravation, and be happy!
• Beware of your dish washing detergent. Use the Environmental Working Group database on cleaning products to find out if your dish washing soap is safe to use. Many common dish washing detergents contain formaldehyde, a known carcinogen. http://www.ewg.org/guides/cleaners

Investigate energy ratings. The published energy ratings of appliances are “best case” reports. When shopping, ask yourself how often “best case” turns out to be the rule in regular usage.

In the US, much is made of Energy Star ratings. There is often less there than meets the eye. The government gives ES ratings for classes of appliances. They award the rating based on best efficiencies within the class. A gigantic humongoid energy-wasting refrigerator equipped with every possible doodad (ice makers, automatic defrost, large cubic capacity, ice water dispenser, tooth brush, back massage, cocktail mixer, etc.) may be Energy Star rated and thus the best gigantic humongoid energy-wasting etc. in its class. From a permaculture design viewpoint, it is still an energy pig. You can smear lipstick all over it and it will still be a pig.

Pop quiz! How many times have I discussed this problem with Energy Star ratings? What does that suggest about Energy Star ratings?

There’s no free lunch. Gee whiz energy consuming doo dads consume energy. It’s what they are designed to do. If you want to use less energy, you need fewer gee whiz energy consuming doo dads in your life and you need more efficient doodads for the ones you feel are the necessary keepers. Here are your choices:

• Use more energy wow-gee-whiz-doo-dads, consume more energy, pay more money, do more harm to the earth and to the future.
• Use fewer energy wow-gee-whiz-doo-dads, consume less energy, pay less money, do less harm to the earth and the future.

Use natural materials. Particle board cabinets can out-gas formaldehyde and adhesives for years. Noxious and dangerous chemicals are common sights on the ingredient lists of many household cleaners. A better idea is to use natural materials as much as possible in your household food system structures and supplies. Find used cabinets made from natural materials. If all you want is an aesthetic make-over, just replace the fronts of the cabinets and drawers, keep the existing structure in place.

Alternatively, if you have money to spend, support a local craftsperson to build you some cabinets that will last into your children’s lifetime. Use local wood or local recycled heritage woods.

Go natural and nontoxic for counter tops. See the Buyers guide to green counter-top materials at http://greenhomeguide.com/know-how/topic/3.

Find safe substitutes and nontoxic suggestions for household products at http://www.inspiredliving.com/health/envir~non-toxproducts.htm.

Use real dishes and serving ware, cloth rags and napkins instead of paper and plastic.

Never bring Styrofoam into your house or onto your property except to use as homemade insulation in your attic or along your walls.

More ideas are in the Additional Resources document for this section.

Ceiling fans in the kitchen? Absolutely and if it’s a large kitchen, you want more than one. Ceiling fans are a great low power way to circulate the air.

Small batteries. You may use some small batteries in the kitchen. Small batteries are a serious environmental problem, and we should work to minimize our reliance on them. You can reduce the harm by using rechargeable batteries, and go one step further by using a solar battery charger. I have several small battery chargers that I bought online from C.Crane Company. I have used these for years and they continue to work fine. They will charge up to a D size battery.