Managing your heat pump

The low temperature last night was 14 degrees F. When it’s that cold, I obsess about how to keep the house decently warm as frugally as possible. I also obsess about wear and tear on my heat pump.

Heat pumps are an efficient source of heat — except when it’s very cold. Heat pumps don’t create heat. Rather, they extract heat from the outdoors air and move the heat into the house. When it’s relatively warm outside — say, when the temperature is in the 40s — this doesn’t take much work and thus doesn’t use much electricity. However, when it’s 14 degrees outside, there’s less heat in the outdoor air to move inside, so the heat pump must work much harder. All heat pump systems have a backup form of heat that kicks in when the outdoor unit can’t keep up with the indoor thermostat’s request for heat. Most heat pumps, like mine, have electrical coils that heat up (like a toaster) and provide this backup heat. This is called resistive heat.

If the temperature outside is in the 40s, then the heat pump is up to three times more efficient than resistive heat, an energy savings ratio of almost 3 to 1. If the temperature outside is 14, then the heat pump is no more efficient than its backup resistive heat, a ratio of 1 to 1. This relative efficiency is called the coefficient of performance. It can be graphed as a curve in which efficiency rises with the outdoor temperature. (See graph below.) At low outdoor temperatures, when the heat pump is no more efficient than its backup heating coils, then you might as well use the heating coils and save the wear and tear on the heat pump.

If you read some heat pump forums online, you’ll find lots of debate about how to manage your heat pump with this efficiency in mind. Most people will say that you should just set your thermostat lower at night but otherwise leave things alone. The heat pump’s control mechanism, they say, can decide for itself when to switch on its backup heat.

I disagree.

Last winter I followed this just-leave-it-alone advice. On a night when the outdoor temperature dropped to about 11 F, the heat pump ran almost all night. In the morning, its coils were covered with ice. This is regarded as normal. If the outdoor unit ices up, the heat pump will “reverse” periodically and melt the ice.

But I can’t help asking myself, why should I let my heat pump grind all night when it’s severely cold, and ice itself up, when at those temperatures the heat pump is no more efficient than its backup heating coils?

I’ve been experimenting. All heat pumps (at least the newer ones) have a position on the thermostat called “EMHEAT,” or emergency heat. The so-called emergency heat is the heat from the backup heating coils. But why should I think of it as emergency heat? It can be used as emergency heat, of course, if the outdoor unit fails and you’re waiting for repair. But why not think of it as heat to be used when it’s so cold that the outdoor unit’s efficiency drops to 1 to 1 (the same as the emergency heat)? There are clear advantages: The outdoor unit just stops — no wear and tear. A heat pump struggling to produce heat in severe cold will grind on and on, and the air coming out of the ducts will be barely warm. Whereas the “emergency heat” will be toasty warm and won’t have to run very much.

Last night, knowing that it was going to be really cold, I set both my thermostats to EMHEAT. I set the downstairs thermostat for as low as I could bear — 55. I set the upstairs thermostat (my bedroom is upstairs) for a bit warmer — 60. During the coldest part of the night, the heating system would start up about every 20 minutes or so, run for three to five minutes, then switch off. I found that much more acceptable than having my heat pump grind and blow cold air all night.

This morning, when the outdoor temperature climbed back to 26 degrees, I put the system back to normal. Right now, at 11 a.m., I’ve brought the temperature up to 65 degrees upstairs. It’s 59 degrees downstairs. I won’t bring the downstairs up to 65 degrees until later this afternoon, when the temperature is higher outside and providing heat is cheaper.

I have no doubt that the “experts” on the Internet forums would say that I’m diddling and that I should just let the system use its own logic. But the problem is, the system’s logic is very crude. It doesn’t even know what the outdoor temperature is. I don’t know what the system’s rules are for when to resort to the “emergency heat,” but it may be as simplistic as “if the thermostat is requesting heat, and if the temperature in the room is still dropping, then turn on the ’emergency heat.'”

I can imagine much smarter algorithms that would consider the outdoor temperature, the unit’s efficiency at that temperature, the difference between the outdoor and indoor temperature, the temperature of the air blowing through the ducts, the actual temperature of the room, and the temperature requested by the thermostat. This could produce a nice balance between the competing factors of efficiency, cost, and human comfort. I’m sure that large commercial systems do have more sophisticated control systems. But until residential systems do, I’m going to diddle with the controls.


The green line shows typical heat pump efficency as outdoor temperatures rise. Note that the heat pump isn’t significantly more efficient than resistive heat, or emergency heat, below about 25 F. The COP scale is the coefficient of performance, described above. Graph by Colorado Springs Utilities

Guess who's coming back…


Ken in Durham

Ken Ilgunas will soon return to Acorn Abbey. He’ll arrive on Dec. 17 or 18 and remain all through the next semester at Duke. He doesn’t have any classes next semester. He only has to write his thesis, and Acorn Abbey is a nice, quiet place for writing.

We’ll also have some outdoor projects to blog about. We’re planning a big vegetable garden next year, new wildflower patches, and we may even get started with beekeeping. The beekeeping project just depends on how much the start-up costs add up to. I’ve bought and read Beekeeping for Dummies, and frankly it all seems rather complicated. But Ken joined a beekeeping club at Duke and has gotten a bit of experience with bees. We’ll see.

Having company also is the only excuse I need to decorate the house for Christmas. And having just read his most recent post on his blog, it’s clear what I need to get him for Christmas — some laundry soap and extra clothespins.

Fixed-position cell phone service


The Telular SX5T fixed wireless terminal

Because I’m a communications nerd, and because of the problems that go with being well wired when you live in the sticks, the communications devices I use are not typical. Though I could get an ordinary land-line telephone easily enough, I’m too far from the central office to get DSL, so I figured, why bother getting a land line and putting up with yet another ditch across my yard if I can’t get Internet service on it?

I’m very happy with my 10-pound Motorola M800 digital bag phone. It’s on the Verizon network, and for more than two years it has been my only telephone. Its audio quality is almost as good as a land line, and with its external antenna, etc., it will get a strong signal where more portable cell phones fail. But a 10-pound cell phone is not exactly convenient as a home phone. I have to run up and down the stairs to answer it. I also wanted a telephone that visitors can use that behaves exactly like an ordinary telephone. For safety, in my opinion, visitors ought to be able to dial 911 from a familiar phone. And of course I’d like to have telephone extensions in the kitchen, bedroom, and radio room.

A company named Telular makes excellent products for this, and I knew that the Telular SX5T was what I needed. The concept of how it works is simple enough. It’s a cell phone, with a good transmitter and a proper external antenna, but there’s no handset and no buttons. Instead, you plug it into your house’s telephone wiring system. The Telular SX5T then puts a dial tone onto your house wiring, and any phone in the house can then make and receive calls. It works just like a regular phone. You can even use it with fax machines. You can have up to five telephone extensions on the house wiring that the device plugs into.

I’ve kept my Motorola bag phone active. I “added a line” to my Verizon service, so the bag phone and house phone share minutes on a Verizon family plan.

The retail price of the Telular unit is $700 or more. However, they often can be bought on eBay at a very steep discount.


My vintage, cinnabar-colored Bell System telephone, which I used for many years in San Francisco, is now working again. It doesn’t even know that it’s now a cell phone.

Chickens and grass

Every morning when I let the chickens out, they head straight for the grass and start grazing. I had never really thought of chickens as pasture-loving grazing animals — they’re scratchers. But they love to graze.

I tried to do some research on chickens and grass to try to understand how they can digest grass and what part grass plays in a natural chicken diet. Authoritative sources were scarce, but one source says that chickens will eat up to 30 percent of their calories in grass. They cannot, apparently, digest the cellulose in grass the way cows and other ruminants can. But if the grass is young enough and tender enough, then the chickens can get a lot of food value out of it. Obviously their gizzards grind the grass very effectively and their digestive systems break it down, because there is no sign of grass in the chicken poop.

Grass has a lot to do, it seems, with the nutritional superiority of eggs from pastured hens vs. commercial factory hens. According to Mother Earth News, eggs from pastured hens have much more vitamin D, 1/3 less cholesterol, twice as much omega-3, 2/3 more vitamin A, 1/4 less saturated fat, and 7 times more beta carotene.

I’m hoping that the winter rye grass I planted as a cover crop for the garden will supply the hens with greens for most of the winter.

Part of the miracle of farm ecology is the way farm animals can make human food out of things that are inedible by humans — cows make milk from grass, for example. But chickens, as long as they can run free, can work this magic as well. It’s nice to think about how some of the energy and nutrition in my eggs comes from the grass growing up the hill and not just from laying mash bought at the mill. Even in December, the chickens are still finding plenty of their own food inside the fence around the garden and orchard — about 10,000 square feet. Right now they eat only about half as much laying mash as they do if they’re kept in the coop. During the summer, when bugs were plentiful, the hens’ mash consumption dropped by probably three quarters. Clearly they’ll eat what they can find first and resort to laying mash only as necessary.

Homemade vegan sausages

I don’t think I’ve ever known anyone who didn’t like sausage. It’s a miracle that someone figured out a way to make the nasty bits of pig taste good.

Lots of people don’t want to eat those nasty bits, though. Morningstar’s vegetarian sausages are very good. Like the real thing, I don’t think I’ve ever known anyone who didn’t like them. But they’re also very expensive.

Many vegans make their own homemade sausages. If you Google for recipes, you’ll find many of them on the web. The ingredients vary a great deal and usually include a legume in some form mixed with wheat gluten (also called vital wheat gluten — same thing). I haven’t seen a recipe which, like mine, uses cooked soybeans.

Here’s how to do it. As usual, this is an outline, not a measured recipe. Improvise according to your own taste…

Cook some soybeans in a slow cooker until they’re soft and turn a medium brown. This probably will take 18 hours or more. Drain the beans and put them into a food processor. Don’t process them into a puree. Leave some texture. Mix your sausage spices into the beans. I prefer a breakfast sausage — sage, red and black pepper, dried garlic, dried onions, and other spices in smaller quantities. Add some salt and some olive oil. Stir all that really well. Then add the wheat gluten (it’s like a flour). Stir that well, then add water until the mixture is moist, like bread dough, and holds together pretty well. Mix it all very well. Today I used about 3 parts soybeans to about 2 parts gluten. Half of each would work fine.

Make logs of the mixture and put it on a square of aluminum foil. Wrap it up in a log shape and twist the ends of the foil. Then steam the logs for 30 or 40 minutes.

When the logs are cool, you can slice them into sausage patties and brown them gently in olive oil.

Chocolate applesauce cake

For more than 50 years, this has been my favorite cake. My mother first started making it when I was in grade school. I’ve had it as a birthday cake more times than I’d care to count. But since today is Thanksgiving and tomorrow is my birthday, that seemed like occasion enough to make a particularly sinful version of the cake.

I’ve found that this cake loves to have nutmeg, or cherries, or both, in the icing. So to the plain white icing (butter, powdered sugar, vanilla, and soy milk) I added nutmeg. I also threw in some chocolate-covered cherry cordials and let the mixer chop the cherries and chocolate into the icing.

The remarkable thing about the cake itself is that it contains no eggs. The only liquid ingredient is applesauce. This makes a dense, hearty cake that stays moist for a long time and keeps well. My recipe is written in pencil on a very old piece of notebook paper. Here is the bare bones recipe. Experienced cooks will know what to do with it.

Cream together 1 cup of sugar and 1/2 cup of butter (I use olive oil instead of butter). Add half a cup of cocoa and mix well. Then add 1 and 1/2 cups of applesauce and mix again. In a separate bowl, sift together two cups plain flour, 2 teaspoons of baking soda, some cinnamon, and some nutmeg. Fold the flour mixture into the other ingredients.

Put the batter into two 9-inch cake pans that have been buttered and dusted with flour. Bake at 350 degrees for 15 to 18 minutes, until a toothpick stuck into the center of the cake comes out clean.

Many years ago, in Sausalito across the Golden Gate Bridge from San Francisco, I won a Valentine’s Day chocolate contest with this cake. For the icing on that cake, I chopped lots of maraschino cherries into the icing and made the icing pink.

It’s also a vegan cake if you substitute olive oil for the butter. I’ve never tried it, but you probably could substitute coconut oil for the butter in the icing.

Kedgeree

I’ve mentioned before on this blog how much I’ve enjoyed the Two Fat Ladies cooking show, which I’ve been watching on DVD. Mostly their cooking is far too meaty and too heart-stoppingly rich for me to want to cook or eat. But I watch them for inspiration, and for insight into the roots of American cookery, much of which comes from the British Isles. The show also is a good travelogue, and good comedy. Their joy in cooking, and the cultural experience they bring to it, make the series a must-see, in my opinion.

They were in Yorkshire on one show, and they made kedgeree using smoked haddock bought in a village fish shop. The kedgeree actually looked quite good to me. I’ll not find smoked haddock around here, but those of us who live inland and who often use canned fish are always looking for new ways to use canned fish other than salmon cakes or tuna salad. In particular, now that we know that sardines are very good for us, it occurred to me that sardines would work nicely in kedgeree. There are a jillion ways to make kedgeree, but the defining ingredients are rice, smoked fish, onions, something green (such as fresh herbs) and boiled eggs. I left out the boiled eggs, having had an egg for breakfast. Chopped celery was the handiest green vegetable I had. I used lots of garlic.

The kedgeree was excellent. Those strong flavors love each other.


Sardines, onions, garlic, celery, and leftover rice

Black Twig apples


Black Twig apples straight from the orchard

I was watching an episode of the Two Fat Ladies cooking show last week (I’ve been working my way through the entire series on DVD), and they were making a dish with apples. One of the ladies said, “But don’t use Golden Delicious. They have no flavor.” Then they had a little discussion about how Americans don’t know much about apples.

I couldn’t agree more. I make the same complaint all the time, especially when I pass the apples in the grocery store. I’ve probably said it a thousand times. Apples must be ugly. “Pretty” apples are bred for grocery stores.

Some people also would be afraid to buy an apple with a name they haven’t heard of. They want the mass-market varieties — Golden Delicious, Winesap, Granny Smith, etc. They’ve forgotten the names of the old home-orchard varieties.

I bought my apple trees from Century Farm Orchards in Caswell County, North Carolina. I had to make a trip there today to pick up two apple trees I had ordered — two two-year-old Arkansas Black trees to replace two young trees that died during the summer. Century Farm specializes in old Southern varieties of apple trees. I have 10 apple trees in my little orchard, and they’re a mix of old Southern varieties: Arkansas Black, Limbertwig, Kinnaird’s Choice, Mary Reid, Smokehouse, Summer Banana, William’s Favorite and Yellow June. I also have a Pumblee pear tree from Century Farms. The trees were planted in 2008. I’m not expecting the trees to be mature enough to bear apples for probably two more years.

Winterscape returns

A rather violent storm blew through during the night. It was the strongest wind I’ve yet seen at the abbey. The rain was blowing sideways for a while, hitting the windows by the bucketful and running off in sheets. There was an impressive light show made by the lightning through the upstairs gothic window. Lily, the cat, ran and hid in her secret hiding place inside the overstuffed chair.

The wind blew almost all the remaining leaves off the trees. This morning, the woods, for the first time this year, are winter woods.

The grass looks fantastic. I’m smug about the fact that my grass is still very green, while almost everyone else’s has turned brown. I’m not sure why this is. No doubt it has something to do with the turf repair Ken and I did in late August. We reworked the bare spots and flung quite a lot of seed, lime, and fertilizer. But I also think that my grass has nice, deep roots and thicker growth. Maybe it’s payoff for the trouble I took to preserve my topsoil after the pine trees were removed early in 2008. Or maybe it has something to do with the fact that I’ve sowed many different types of grass seed during the past two and half years, hoping that the variety best suited to any particular spot would take over there. I’ve always sowed nitrogen-fixing clover along with the grass. And maybe it’s because I don’t mow it too close the way most people do. I was conflicted about having a yard to mow and was highly tempted to let it all run wild. But if you’re going to have turf, it ought to be good turf. I believe I have mastered grass farming. Now on to other things.