Monthly Archives: March 2010

school bullying in the news in MA

2 sad bullying stories in the news this week in MA:

$35M lawsuit: Lynn failed to protect bullied kid

South Hadley: Prosecutors: 9 teens charged in Phoebe Prince death

To these communities and families and friends of all involved, my heart goes out to you.

ObComment: Many of our schools are broken. Bullying is a symptom of deeper problems. Not just with our schools, but with our communities, families, society. Schools are just a mirror. But still a good place to start!

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PBDEs in the mainstream press…

Flame wars — Fire retardants may affect female reproduction
“In North America, PBDE concentrations in humans have been doubling every four to six years since the 1970s, and are 20 times higher than in Europe.”

“I hope you are not nervous, but this concentration is very high,” Bergman says with a light Swedish accent. My blood level of one particularly toxic PBDE, found primarily in U.S.-made products, is 10 times the average found in a small study of U.S. residents and more than 200 times the average in Sweden.

And the not mainstream…

Dell, Apple (I think) and some other companies stopped using PBDEs in their plastic before mandated by law.

“[M]attresses, mattress pads, couches, easy chairs, foam pillows (including breastfeeding pillows), carpet padding, and other foam items purchased before 2005 are likely to contain them [PBDEs].”

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PVs and grid-parity — we’re basically there in MA

One interesting thing about PVs right now is that it is getting VERY close to it being cheaper to get one’s electricity from PVs rather than one’s local electric company.

Some discussion:
1. Electricity in MA (especially if you are doing GreenUp, GreenStart, the Wind Fund, etc to be 100% renewable sourced) is basically 20 cents per KWh. Or more. In other words, expensive.
2. Electricity in MA (and New England generally…) is fairly dirty unless doing GreenUp. The mix (last I checked in Feb 2010) is roughly 1/3 coal, 1/3 natural gas, 20% coal and oil, 10% renewables, 10% “other”). Anyway, the basic point is it’s not very green yet.
3. The grid-parity calculation I did in excel is even without factoring in state and federal subsidies and things like S-RECs (where the state pays you $0.38/KWh produced for the “greenness”…)
4. There is pretty decent sun in MA. The quick calc that seems to get used is that if your panels are basically facing south, you take 1200 * system size, and that’s the number of KWh produced in a year (So a 6KW system makes 7200 KWh (an ave of 600 Kwh/month).
5. We don’t happen to have net-metering here in Stow, because our electricity is thru a “municipal”… Hudson Light and Power… and they don’t do net metering yet. Soon I hope! What this means is our payoff calculations get a little trickier since we will have to pay pull price for electricity we use when it’s dark or cloudy.
6. Since we are adding PVs directly to a house we are buying/building, it gets rolled instantly into the 30 year mortgage, so… the basic cashflow calculation is that we are paying a little more for our mortgage with PVs, but our reduction in electricity bills offset this increase. So we are cashflow positive from day one.
7. A more complicated analysis would factor in opportunity cost (what the $ could be earning in investments) and tax-deductions for mortgage payments. But also the subsidies.
8. Protected from grid-electricity price increases!

In the end, I don’t even care so much about $ payback periods. I would MUCH rather use the sun than fossil fuels. So it’s worth it even if my calcs are off slightly and it’s not quite a money maker.
But we really are there. So if you’ve got some sun, it’s time, or just about time to go solar in MA.

FWIW… I would advise someone ready to “wade in” to just ask to use PV microinverters… you can easily gradually increase the number of panels without problem. And partial shade is not a problem with microinverters.
So start small and add more later!

And insulate your house a little more first! That will probably save you even more money! At least in MA! “Energy audits” from your electricity or natural gas company are usually free. And insulation improvements are subsidized as well.


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Filed under contrarian, erik-green, solar, technology

Unschooling and interning…

“[D]irect soliciting of fascinating adults is compatible with the unschooling (and, generally, homeschooling) philosophy of “learning from the world” and ignoring arbitrary age barriers. Why, then, do so few teens attempt it?” LINK

Basically, my sense is poking around in internships and such is never going to work out, but if you are really obsessed with something, you can probably just dive right in. That might mean some advanced schooling or mentorship. But it may not. Just depends.

– “The Loneliness of the Information-Age Learner: Students’ Ability to Pursue Knowledge as it Relates to a School’s Size” (from: Reflections on the Sudbury School concept (1999) page 219-228 (excerpt: “Nor was it realistic to assume, back in the late 1960’s and during the 70’s and 80’s, that there would be lots of opportunity in the outside community for our students to move in and out of learning situations… Use of outside resources was harder in reality than we had pictured in theory…” (p 220-1)
– John Taylor Gatto often talks about how he was able to line up internships/apprenticeships/mentorships/coops for many of his students — but I don’t see how this is widely possible. Maybe I am wrong.
– “Where then is the dividing line between childhood and adulthood? The question appears to be even more obscure…” (A New Look at Schools‎ – Page 38)

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Filed under alternative education, contrarian, education, school, Sudbury Schools and Sudbury Valley School, unschooling

Lotsa Helping Hands

This is an amazingly useful website for helping friends/family/neighborhoods/religious communities/cohousing/etc organize help for a person or family in need. It’s basically a custom calender and bulletin board system for communicating with a group of helpers so you can organize and assign things that need doing. Anyway, enough said… just thought people should know about it. It’s such an obviously useful website, yet it’s amazing that there is nothing else like it. What a great help! (I helped with some coding on this website years ago.)


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Our car (a 2001 Saab 9-5 wagon) gets pretty good gas mileage without thinking about it much. Seems like we average around 26 MPG in our typical around-town driving, and on the highway (without racks or roof-top boxes) about 31 MPG. That’s partly why we chose it… most minivans and SUVs get considerably worse gas mileage. But where was I… when I am driving to and from school, if I reset the car’s little computer readout which shows AVG gas-mileage, so I am then looking at just the current trip, I can get around 40 MPG. Nice. So just now I got to wondering… is there anyway to get a readout like the Priuses apparently have showing real-time MPG to aid in my hypermiling on a regular basis — without having to constantly reset the Saab’s computer (a bit of a pain)? Yes! Here it is! SCANGAUGE II

Oh, and I just am reminding myself to check my tire air-pressure and to screw in those little cheap thingies that show you GREEN when your pressure is ok for a given tire — apparently tire pressure matters quite a bit too. Sure there will be some time to pay off the expense, but my guess is the breakeven point wrt fossil fuel use, emissions, etc (vs $$) is incredible quick even if one is able to dial back ones fuel use by even a small amount like 5%. For us, driving 12k a year at an average of ~26MPG, that’s 462 gallons of gas. Visualize 462 gallons of gas. (Google tells me that 462 gallons is 61.76 ft^3. So that’s a cube of almost 4 feet by 4 feet by 4 feet.) Yikes!

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Filed under car, erik-green, technology

We can heat our house with a hair dryer. Is that inexpensive?

The house we are building here in lovely Massachusetts, USA… almost a Passive House, but not quite certifiable… well, we can heat it with a hair dryer (1500 W of heat). And two on a very cold day (6F design temperature). Does this mean our heating bills will be low? Pretty low, I imagine, yes. But not zero.

Let’s do some math… And first let’s simplify things… the HDD (heating degree days) for Stow, MA is somewhere around 7200 (base 68F) meaning that if you multiply the days of the year we need heat times the temperature differential between the inside and outside temperature on these days, you’ll get 7200. It’s a little more exact than this (think “area under the curve” from calculus — using hour by hour measurements), but that’s the basic idea.

So let’s simplify it even more. Let’s call every winter day exactly 32F outside vs 68F inside and assume our 1500 W can keep up with that (which from my back-of-the-envelope calculations seems about right…) So that’s a delta of 36F. Now how many days is that? 7200 F*days / 36 F = 200 days = 6.66 months. Let’s go crazy and call it 7 months.

OK, so let’s say one really did run a hair dryer for 7 months, 24 hours a day. What would that cost to run 1500 W (1.5kW) that whole time? Well, we pay $0.20/KWh. So using the factor-label method to keep track of our units… making sure numerators and denominators cancel out, that’s:

7 months * 30 days/month * 24 h / day * 1.5 KW * $0.20 / KWh = $1,512.00 per year

In other words, kinda a lot!!!!

But that’s why people don’t typically use electric heat, it’s expensive. (It’s also not a great idea because fossil-fuel power plants are roughly 33% efficient in converting the fuel to electricity… I imagine that’s exactly why it’s expensive! So… it’s better to use it in direct form at your house…) That’s where the heat pump comes in. If we factor in the 2.7 COP (coefficient of performance) of our Mitsubishi “Mr Slim” air-source heat pumps that’s:

$ 1512 / 2.7 = $560

OK, now we’re talking! This also happens to be almost exactly the number you would get if you calculated the cost of delivering 1500W of heat via propane or natural gas. That would be fine and dandy too. So the 2.7 COP mainly serves to green up the electricity use, getting back to parity with using propane directly. 2.7 * 0.33 = 0.8991 (probably about the efficiency of a Rinnai propane direct-vent heater)

Now, the reality is that I hope most of this heat comes from active solar heating. But more on that later!

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Filed under building science, erik-green, house, money, passive house, solar, superinsulation