Here’s a neat idea from Portland: Sunnyside Neighborhood Energy. It’s a district thermal-energy plan being shopped around by some folks who think they’ve solved several problems at once.
The problem? The neighborhood’s old elementary school with oil-fueled boilers from 1917. Also, that climate thing that Al Gore keeps going on about. Plus, low income families often struggle to pay their utility bills.
The solution?
SunNE, would be centered at Sunnyside Environmental School, where a central plant would replace the school’s 1917 oil-burning boiler with a solar-powered geothermal heat pump. The plant would then connect to a network of underground pipes circulating through the surrounding 38 blocks. The system wouldn’t supply electricity to the neighborhood but would supplant the electricity and natural gas used to power hot water heaters and air conditioners.
Okay, I’m in love.
As you may know, I looooveheat pumps, especially those of the ground source variety. In a residential setting, a small electric motor comparable to the one in your fridge can extract enough heat from underground beneath your yard to provide you with unlimited carbon-free heating and cooling. All you pay for is the installation, a little periodic upkeep (like you would for a furnace anyway), and the power to run the motor. That’s seriously awesome. If you run the motor with solar then you’re really cooking.
SunNE is taking that basic idea and multiplying it. By installing a network of pipes they can essentially put everyone in the neighborhood on the same carbon-free grid. It’s not that SunNE can magically make everything better, it’s just that…
Well actually, it really can make a bunch of important stuff better.
In any case, it’s a great example of a locally-scaled idea that can yield benefits both now and in the future. This is exactly the kind of thing that a smart economic stimulus package would target. It would create green jobs now—designing the system and performing the installation—and it would make energy more affordable for the neighborhood while doing a reasonable bit to reduce climate emissions. For an estimated price tag of between $7 and $9 million, I’d say it’s a bargain.
There’s plenty more information on the City of Portland’s website here. You’ll also find a fair treatment of the problems, which are mainly related to the upfront costs and the disruption of installing the system. Then you should also check out SunNE’s wikispaces page for all the rest of the details.
If you want to help get the project off the ground, you can check out their Ideablob. (And here’s a nice article in the Oregonian too.) Even better, executive director John Sorenson tells me that Northwest Neighborhood Energy is hosting a dance and fundraiser on January 31 from 7 to 10 p.m. You’ll even have a chance to check out the 90-year-old boilers while you’re at it.
Hat tip to Cy Berryman at Northwest Energy Coalition for clueing me in to this project.
Lacey
From May to July of 2008 I had the pleasure of creating my own summer “green job” by co-developing the Northwest Institute for Community Energy (the NICE) thanks to a grant from Clif Bar. With the enthusiasm and help of 3 other fellow peers who are as dedicated to building a more sustainable, just, and prosperous future as I, we worked with directly members the Sunnyside community to build support for this solar thermal project. This community has been nothing but inspiring, and after my friends and I had to return to school/work for the fall, our Sunnyside friends started their own non-profit– Northwest Neighborhood Energy (N2E)– so they could harness the momentum of excitement for this one-of-a-kind project, as it’s truly a means for direct collective action for maximum impact. After all, it’s pretty powerful to change a light bulb, but it’s REALLY empowering to help 38 blocks reduce their carbon impact by 70%! And just think: what if communities all over the U.S. did something similar to what Sunnyside is doing– the nation would have localized solutions popping up everywhere (keep your eyes peeled, I think you know what I’m doing next summer!) :)Projects like the SunNE truly define and build a community’s morale in time of such great climate uncertainty. And while I’m not technically a neighbor of Sunnyside, I sure feel like one. I cannot express how proud I am of this neighborhood; their dedication to revitalizing Sunnyside Environmental School’s facilities while “steeping” the young minds of their students in the process shows how engaged citizenry can make tangible improvements in people’s lives and futures. Also, please note that Coldest Day of the Year Energy Festival and Dance is actually ON JANUARY 31ST FROM 7-10 P.M. (not January 21st as previously stated).
Eric de Place
Oops, sorry about the typo in the date! I’ve corrected it.
John Sorenson
Thanks for the great article-getting the message out, sustainable, community ownership, carbon neutral, relocalization. At Northwest Neighborhood Energy, we’d like to help empower other neighborhoods based on the SunNE model. Lacey and TheNICE students certainly helped to get the message out with their institute. Our two fun projects in the short term: IdeaBlob, We’re in the finals! Please vote for us between Dec. 22 and the 31st and send the link on to your friends. We have a shot at $10K! #2,”The Coldest Day of the Year Dance”. Come dance and support the project along with Secretary of State Bill Bradbury, State Rep. Jules Kopel Bailey, Councillor Rex Burkholder, and Lacey Riddle. Real community energy. Thanks.
Erin
OK, so this is probably a dumb question, but I’ve never understood it, and the link from the article didn’t help. How can a ground source heat pump do anything other than heat the house to ground temperature? Which should be equal to average annual temperature. Where I’m sitting, that might be about 40 degrees or a bit less. In Portland, I don’t know, maybe 50? How does that work without another heat source on top of it?
Matt the Engineer
(dawns engineering superhero cape) A heat pump is a device that simply moves heat around. Heat can be pulled from this 40 degree water, cooling down this water and heating up something else. Heat pumps generally use a refrigeration cycle to do this. Imagine a substance with a boiling point of, say, 35 degrees is put in metal tube, and this tube is placed in 40 degree water. This substance (called a refrigerant) will boil off. Since evaporation is a heat absorbing process, the 40 degree water gets a bit colder as the refrigerant boils off. Now, instead of just letting the stuff boil away in the air, let’s run the tube to another container of water – say at 100 degrees. Now if we compress this vaporized refrigerant enough, we can get it to condense (turn back into a liquid). We do this using a pump (called a compressor), and since condensation is a heat rejecting process our hot water gets hotter. When we then return this refrigerant to the cold water (through a blockage with a small hole or “orifice” within the tube to reduce the pressure), it’s ready to start the cycle over again.The result of this that you get a lot more bang for your energy buck. Instead of using, say, 1 kilowatt of energy to directly heat a space you can use that same kilowatt of energy to move, say 3 extra kilowatts of energy from the cold water to the hot water.
Hal
Thank You Mr. Superhero,The next question: Isn’t there a limit to how cold this portion of ground can be dropped? If we all were able to heat our space this way, is there enough replacement heat from the earth’s core to replace? Is that sustainable?
Matt the Engineer
The temperature you want to avoid reaching is 32, since that’s when water turns to ice. So you need enough mass in your heat source to make sure that it will stay above 32 for an entire heating season, given the amount of heat you’ll need to take from it. But where does the heat come from? Unlike the other technology called geothermal energy (ground loop heat pumps are also called “geothermal” heat pumps, which is confusing), which actually mines heat from the earth’s core*, a ground source heat pump gets most of its heat from the environment. After a winter of pulling heat from the ground, the ground around your system is a bit colder. But then summer comes along and warm air and sunshine heats the ground back up.* I can’t imagine the time scale you’d need to actually start cooling the earth to an appreciable amount using geothermal energy plants, but I’m sure it’s very very long (if ever) and geothermal energy production is considered to be a very green technology.
Erin
Thanks superhero, that makes a lot more sense.So, this type of system would probably work best in warmer places, where the difference between ground temperature and freezing temperature is large. Where the difference is small, a larger system would be needed?Would it work at all in permafrost areas? (folks living in leaning houses on melting permafrost might appreciate cooling their ground further)And if you suck out heat in the winter, but don’t add any back in the summer (beyond what will naturally be added by the sun), won’t you slowly lower the soil temp over time, so your system will be less efficient the more years you run it?
Matt the Engineer
Yes, to avoid freezing you would need a larger ground loop in regions where the ground gets very cold.I’m no expert on permafrost regions, but I would imagine the initial problem would be digging for the ground loop in the first place. But if you overcome that, you could use glycol (anti-freeze) in your ground loop and just use a larger loop to account for the ice that would form.I’m not aware of the “lower soil temp over time” issue being that big of a deal. Just as your ground loop conducts heat from the soil, soil conducts heat from other soil around it. We certainly have to be careful about multi-year effects, but upsizing a bit solves most issues.
Dixon
Erin’s questions are good, but the blanket answer to the “how does the heat flow balance out” belongs to a good computer program. In the summer, you “feed heat” into the system by air conditioning your house. All that heat that used to blow away into the air in that noisy compressor outside your window now silently goes underground to be used in summer. Very simple computer operations watch the heat flow and makes sure there will be enough to heating in winter, and cooling in summer. If the program doesn’t like the heat flow rates, the operator gets an email and actions can be taken (automatically turning thermostats up or down for example). But like “superhero” implies, if you have a capacity problem heating the earth up with only 38 homes, you’ve got other issues to worry about.