While I think it is a worthy goal, I seriously doubt they will even achieve 50% of the bench mark. When homeowners learn how much this will add to the cost of construction and that the ‘payback’ will be measured in decades they are going to balk.
http://www.customhomeonline.com/industry-news.asp?sectionID=204&articleID=930454
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Green Building does not have to cost more. I just requires a shift in thinking and planning. As a whole we consumer much more than we probable need to.
In order to think ourselves out of an undesired result, we have to change our thinking.
It is not a matter of "not having to cost more" it just does. And net zero means things like photovoltaic, geothermal heat pumps, wind generators etc. These add considerably to construction cost's. And current tax incentives are just not enough to tip the scales for most people.
Let's do a little math off the top of our heads.
'Net zero' means no net energy input to a house except the greenie alternatives, which is pretty much only wind or solar in MA.
Wind is pretty much out of the question in dense areas, too much shadowing.
That leaves solar. Let's say that there is a miracle and there are cheap quad layer cells by 2030 that get 50% efficiency, or that small solar boilers for solar thermal are developed with 50% efficiency.
Boston average insolation is 3.8 kW-hrs/m^2 per day. Say we do get 50% efficiency with a good tracking system, that leaves 1.9 kW-hrs - m^2 per day. My direct experience with a tracking array on Mt Haleakala in 2004 was that 6 meters sq gave 15kW-hrs per day, or 2.5 kW-hrs m^2 per day, with state of art for 2004 32% cells.
So, 1.9 kW-hrs m^2 per day in Boston may be feasible by 2030. BUT, that is a ;yearly average, so we will say 'net zero' applies to the whole year average. POCOs will go crazy supplying power only in dead of winter overcast days and cloudy sultry summer monsoon days.
My ground source heat pump has a COP of 5.6 for 56 F ground water temp (colder in Boston, so say a COP of 5. Super insulated , air exchange regen, etc. with almost no windows (exept for the governor and politicians of course) can get you to where you only need say 10 kW-hrs per day for heat ( 7000 BTU/hr heating plant, about the size of a window air conditioner, but you cannot open the doors very often). 2 people produce 800 BTU hr, taken into account.
Hot water - say uses only 2kW-hrs per day with full recovery heat exchangers (more cost) and sharing the shower<G>. Say cooking and baking take another 2kW-hrs per day - a plus in winter, negative in summer. 2kW-hours per day for entertainment/electronics.
Thus, you only need to change your living habits a little to acheive a 'net zero' with a yearly average power generation of 16k/w-hours per day.
OH, wait, you now have an electric car that you gotta plug in - nah, public transportation is now mandated, private cars (except for politicians) are outlawed, since the car companies are all dead anyway.
so, 16/1.9 mean you only need 100sq feet or so of solar collector. there is some fakey math there. PEAK power is NOT the same as yearly average solar insolation.
At 50% efficiency, that 100 sq ft array cranks out over 4.5 kW - where does all that go to get stored for the yearly average 'net zero' if everybody is generating power on warm spring days when no heating or AC is needed??? Generate hydrogen for the politicians private cars?)
Price of solar, esp small scale, has stayed constant at about $10/watt (or more) installed since the 80's. 4.5kW *$10 is $45,000 extra per house for 'net zero', even assume there is some magic storage infrastructure then. That $45K does not include the GSHP added costs ($15K today) super insulation and heat recovery exchangers add another few K, pretty soon the small house price has increased 100% - think that is maybe what reinvent is referring to <G>
Not to worry, magic finances will have inflation pass that cost on the the 22nd century chinese?
>>pass that cost on the the 22nd century chinese?
That's why we need to discover life on other planets... tax them to pay for this stuff.
net-zero energy in all new commercial, public, and residential buildings by 2030net-zero energy in all new commercial, public, and residential buildings by 2030
And, consistent with no burn days besides!