Monthly Archives: May 2012

Does anyone know what they are doing?

Does anyone know what they are doing? “Experts disagree.” You hear that a lot these days. In pretty much every aspect of life. Sometimes even in cases where there is ACTUAL DISAGREEMENT! (as opposed to global warming where there is very little disagreement amongst actual expected… as far as I have been able to discern from Real Climate)

It’s pretty humorous. Or disconcerting. (You choose! Experts disagree!) I’m not complaining about incompetence. Things can be COMPLICATED!

Amazon? “Amazon is so opaque, with so many mysterious businesses and revenue streams, that you’ve got to wonder whether the people who work there even understand what it’s up to.”

Green building? “How much insulation is enough?”

Senior traders? Economists? “Once things get to a certain level of complexity, fraud and confusion dominate.”

Doctors? “How many doctors does it take to make an autism spectrum diagnosis?”

Time to be an expert! Happens all the time of course. We hear regularly of the person diagnosed with a rare disease (or their child) having to become “The” expert. And I regularly read of kids doing things as “expert” as building a nuclear reactor (14) or sailing around the world (16).

Why Technical People Should Blog But Don’t

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ethical meat is solar and…

The NY Times “Ethicist” column had a writing contest. The winner: Give Thanks for Meat

??? Yes and No. The killing issue aside–though HOW that is done is also important (Temple Grandin!)–the problem I see is that it is 99.9% impossible to buy such ethical meat in a store. At least Whole Foods pretty much admits that–they have a ranking system 1-5 (5 best I believe?) and one never sees meat above a 2 I think it is (and this is organic). Our biodynamic CSA back in Amherst (brookfield) had once or twice a year meat sales, and this probably qualifies. And backyard eggs.

– solar (limit fossil fuels used in the farming and raising) (Michael Pollan)
– ethical treatment including leading up to and slaughter (Temple Grandin)
– part of a biodynamic process (Brookfield Farm)
– local (again limiting some fossil fuels, and also supporting the local economy)

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Fuhrman: Organic Fruit vs No fruit

Q: “Is it dangerous to eat more fruits and vegetables because of the increased consumption of pesticides? Do I have to buy organic?”

A: “Keep in mind, every study done to date on the consumption of food and its relation to cancer has shown that the more fruits and vegetables people eat, the less cancer and heart disease they have. All these studies were done on people eating conventionally grown, not organic produce. So, clearly, the benefit of conventional produce outweighs any hypothetical risk.” (But he also suggests avoiding the EWG “dirty dozen” if you can and non-organic dairy and beef.)


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Our PECs: site vs source (primary) energy

Another good way to weigh one’s home energy usage is per person. (not arbitrary per sqft or per HDD, etc.). PEC=Primary Energy Consumption. Makes sense if we are trying to be “green”.

That’s what Marc Rosenbaum is proposing here.

If I am understanding the gist of what he is saying it is as follows as applies to us:

1. Here in MA/New England, power plants are about 33% efficient. They waste 2/3 of the energy (mostly fossil fuels) in making a unit of electricity. The exact number Marc uses is 1/2.7, not 1/3. (37% efficient source to site.) So… since we have used approximately 11000KWh/year, that is 29700 KWh/year in source energy that we REALLY used.

(Worry about PVs later… in step 3.)

2. We are 4 people, so look up our “fair share” according to his “people = bedrooms+1” equation and we should be trying to meet 13,600 KWh/year in source energy. For everything… heating, cooling, hot water, appliances, cooking, lighting.

3. One should be able to offset some percentage of hot water and electricity usage from onsite generation. Marc explains (I believe) that the Passivhaus PHPP allows up to 20% offset for a traditional solar hot water system, so in his mind, why not allow up to 20% of electricity use as well. And indeed… we heat our hot water with an air-source heat pump too, so I am lumping it all together. And actually, since I am dealing with real data, not estimates, I see from my record keeping that in the last year we have exported 5600 KWh to the grid. So that is the equivalent of 2.7 that much in “source energy” that we have offset = 15,120 KWh

So if we reduce our 29,700 by 15,120 => 14,580 KWh/year

4. 14,580 > 13,600 KWh (Marc’s limit for 4 people)

So we didn’t meet Marc’s proposed criteria for PEC for a Passivhaus in New England, even assuming my generous PV offset based on our grid export numbers.

Pretty close though. Why didn’t we meet it? I assume:
– Our house is too big (1741 TFA via PHPP)
– 2 of us work at home and waste energy
– Windows and HRV not efficient enough
– We should use more solar thermal heating (I have plans on this front)

‎”Your house is a leaky bucket and the sun is a hose. To raise the water level, you need fewer leaks or a bigger hose.” — Nick Pine in a discussion of his “box on the lawn” solar collector design in

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Our house vs passivhaus / passive house

BTW, as a followup to my last post. Our house misses the passivhaus PHPP standard for Specific Space Heat Demand.

= 4.75*1000*1741/(3412) = 2423 KWh used per year is what the PH Certificate requires as a max for “Specific Space Heat Demand” (for our 1741/sqft TFA)

Give that we *used* an estimated 2300 KWh (2338) for heating, and given we can estimate our (non hyperheat/h2i) heat pumps at 2.25 COP overall (as a 15% adjustment from the “North Carolina” temp zone rating–I think I looked up once for our unit’s seasonal HSPF… 15% adjustment: as they seem to do in Canada since the COP is temp dependent.)

That would be:

5260 KWh of actual heat *delivered* from the 2338 KWh our minisplits *used*.

So we are 1/2 or 1/3 as good as a passive house I guess. Probably 1/3 since it was a mild winter.

So you can see why people think passivhaus might be extreme. We are talking about $350 (our house) vs $120 (a similar-sized passivhaus) in heating given $0.15/KWh electricity. I still think it makes sense, especially since people are getting practiced at doing it panelized/modular. (See Green Mountain Habitat for Humanity in VT for example.)

– roughly 68F max in winter, roughly 78F max in summer
– I should do a per HDD calc

FUDGE FACTORS (+ or -) in my “1/2 or 1/3 as good as a Passivhaus” calc:
– Weather/climate in PHPP is a 30-year avg. This 2011/2012 winter was mild.
– COP of our heat pump is a guess (maybe I guessed way too low?)
– Previously mentioned guess for % (10%) of heat used for hot water heating
– Some inaccuracy of the emonitor device (vs direct submetering)
– Any errors made in the PHPP (our house used a number of non-certified products… windows, HRV so guesses had to be made)
– Related to above… our windows and HRV are also not as efficient as those typically used in a passivhaus.

That said, obviously there are some houses that don’t use Passivhaus” equipment — like this one — that do MUCH better than the PH standard. Occupant behavior matters a lot.

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2011/12: The year in heating

We have an emonitor gizmo that tracks our home energy use by circuit. One circuit is the air-source minisplit heat pump (the heat and cool in the house).

For the YEAR ending April 2012, the heatpump circuit shows:

3,009 KWh (total for year, heating and cooling and some hot water)
2,598 KWh (Oct-Apr — 7 mostly heating months)

Remember that we also heat our water with an air-to-water heat pump in the conditioned basement, so during the heating months, it is stealing heat from the house. So the 2598 includes some of that. Let’s pretend it is 10% of our total load (no idea) so that would be

2338 KWh (Oct-Apr — mostly heating months. HOME HEATING ONLY)

If we pretend the price we pay for electricity is $0.15/KWh (it’s more complicated than just a simple number like that with this and that charges) but close… then that is:

$350.70 (our estimated heating bill for winter 2011/2012)


(Well, and actually… minus some significant fraction of that which is covered by our PVs (electric solar panels). We don’t have net metering, so our electric bill is rarely $0 even in the summer. I just don’t unclude the PVs cause I generally think of them as an offset. Not an important part of the house.)

– The silly 20KWh/month our minisplit uses whether it is on or not. Nothing to do about that at least in the winter. But I could flip the dip-switch for 5 months of the year.
– Someday I will add a submeter for the minisplits since the emonitor is probably 10% off in some direction. (I believe that’s the spec I’ve seen.)
– More PVs, perhaps this string with a central inverter and small battery for:     – night-time (since no net metering) and
    – power outages (we have a well so it would at LEAST be nice to have running water when the power goes out.)

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“High-fat, high-protein diets are also dangerous”…

This is old news, but I think it is worth a reminder! (Do your own research of course, but I think Joel Fuhrman’s advice–based on research of research–is quite sound. His books always include lots of supporting research references to studies one can read oneself on PubMed, etc. And exercise!)


This ill-advised “news”may heve been fit to print, but the diets surely are unfit to eat.
By Joel Fuhrman, M.D.

In July, The New York Times printed an article titled “What If It’s All Been a Big Fat Lie?” by Gary Taubes. Taubes states that the cause of the obesity problem in the U.S. is that Americans eat too many carbohydrates and that low-fat, high carb diets make you fat and lead to other diseases. His solution is the high-fat, high-protein diets advocated by Dr. Robert Atkins and others. After reading the article, I sent a letter to the editor, which the Times did not print. The information that follows was included in that letter.

The recent New York Times article by Gary Taubes perpetuates many of the nutritional myths spread by Dr. Robert Atkins and others. The fact that high-glycemic diets-rich in refined carbohydrates such as sugar, pasta, and other junk foods–are large contributors to the obesity epidemic and also to serious disease in no way justifies a recommendation to eat a diet that is rich in saturated fat. Without question, high-glycemic diets are dangerous, But diets rich in the highly saturated fat of animal products are also dangerous. Why debate which dangerous diet is worse?

Taube reiterated the false claim of authors like Atkins and Barry Sears that Americans are eating less fat than ever before but our obesity rate is skyrocketing. The truth is that because we are eating more calories than ever before, the percentage of fat in the diet has gone down. The total amount of fat in the American diet has changed very little.

Atkins recommends that you eat primarily high-fat, high-protein, fiberless, animal foods and attempt to eliminate carbohydrates from your diet. Analyses of the proposed menus show that animal products comprise more than 90 percent of calories in the diet. Hundreds of scientific studies have documented the link between animal products and various cancers, Increased consumption of animal products combined with the decreased consumption of fresh produce has the most powerful effect on increasing one’s risk for various kinds of cancer.

There are more than 3,500 scientific studies, involving more than 15,000 research scientists, reporting a relationship between the consumption of meats, poultry, eggs, and dairy products with heart disease, cancer, kidney failure, constipation, gallstones, diverticulosis, and hemorrhoids, just to name a few.

A meat-based diet like the one Atkins advocates (which includes little or no fruit, no starchy vegetables and no whole grains) could more than double your risk of certain cancers, especially of meat-sensitive cancers, such as epithelial cancers of the respiratory tract. A study conducted by the National Cancer Institute found that the relative risk of lung cancer was six fold greater in women in the highest fifth. Atkins devotees adopt a dietary pattern that is completely contrary to the one recommended by the world’s leading research scientists studying the link between diet and cancer.

There are numerous ways to lose weight. However “effective” they may be, some simply are not safe. No responsible person would advocate smoking cigarettes or snorting cocaine simply because these can be effective in promoting weight loss. Advocating a weight-loss program based on severe carbohydrate restriction also is irresponsible. following this advice can cost people their lives!

Diets that are designed to be low in refined carbohydrates, while rich in fruits, vegetables, nuts, seeds, and legumes, offer the greatest protection against cancer, and at the same time enable individuals to lose weight healthfully and permanently. My patients who follow a high-nutrient, high-fiber, low-glycemic, plant-based diet invariably achieve more substantial weight reduction, compared to patients who follow the meat-based diets irresponsibly supported by the recent article. Remember losing weight healthfully and permanently is the key to success.

Joel Fuhrman MD: Nearly Everyone Gets Cancer

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Filed under diabetes, erik-green, evidence-based, health, obesity

Portland Bikes

Go Portland. But… other cities/states will struggle for 1/2 the year since many many months are quite cold for biking (and snow and such) so it’s hard/dangerous to bike. How Bikes Make Cities Cool – Portland If one is riding to work/school at 8 am it is very cold in MA even in October. Seasonal temp avgs at if you are wondering. And then in the milder/hot months, you’ll need to shower a lot… at work, school, etc. Which is fine if there is a shower.

Geneva, Switzerland was also great for biking year round.

Dumb places we people live.

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We’d be net zero but…

Our house would be net zero source energy but…

– well filters: we avg 54 KWh / month
– well pump: 10 Kwh / month
– radon fan: 40 KWh / month
– 2 home offices: 60 KWh / month
– Mitsubishi minisplit: 20 Kwh / month (EVEN WHEN OFF DUE TO A COIL HEATER THINGY!)
– electric lawn mower: (not much, but just sayin’)

What else did I forget?

So that’s 54+10+40+60+20 = 184 KWh / month
= 2208 / KWh per year

… that we can’t help that some other net-zero types of house don’t have since our house has a well and 2 home offices and a mitsubishi mr slim air-source heat pump with what I would consider a design flaw!

We use approximately 10,000 KWh per year for everything (heat, hot water, lighting, cooking, etc.) And our 6.9 KW PV panels make about 8,400 KWh so if we didn’t have the extra 2200 KWh, we’d be easily net zero.

BUT… then there is driving. Someone who lives in a city in and walks everywhere is blowing us away. We drive maybe 15000 miles per year at 20 MPG (minivan). There goes net-zero.

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