Energy Efficient

     Green building now offers so many material and design alternatives sometimes it can be overwhelming. Today I would like to run through some of the competing benefits of installing a solar vs a living roof. This would seem to be fairly simple and straight forward but actually many factors are involved. Let's stick with the purely environmental benefits.

-The idea with solar power is that the power you produce on your roof doesn't have to be produced at a coal fired plant or by some other harmful means somewhere.

-The idea with a living roof is little more nuanced- in that you are recovering the space for flora (carbon reduction) which has been displaced by your residence, improving your insulation, cooling your roof, all while mitigating the urban heat island effect.

     So what is actually more beneficial for the environment? Guess what- It is somewhat a matter of perception and is very involved if one is trying to quantify. It comes down to a complicated equation. (doesn't it always?)
First you have to figure out how much power your hypothetical solar roof will create over the course of it's lifetime. Then you figure out how many emissions would be produced if that power was created via conventional means. This is how many emissions aren't being created because you aren't consuming the power that would have necessitated their creation. However the production and disposal (or recycling) of solar panels (and the energy required to do so) creates it's own set of emissions which must be subtracted from that original total-emissions-avoided number. So what your left with is the total amount of carbon emissions which aren't being created due to the total lifespan of your solar panels. This emission reduction is the environmental benefit of your hypothetical solar roof.
     On the green roofs side you must calculate the entirety of carbon emissions and pollution which are being breathed and processed by your rooftop plants in the course of your roofs 40 to 80 year lifespan and ad to that the carbon emissions avoided from the energy savings reaped from your insulatory and roof cooling benefits. The complexity of variables such as plant type and energy-use-avoided are staggering.
That is why I pose the conclusion that it simply isn't generally feasible to quantify/compare the 'exact benefit' of these two alternatives because there are so many ancillary factors involved. There are a few definite things to consider though when making your choice;

•  A living roof is going to be more beneficial in an urban setting in the sense that it provides a place for plants where there is none. This is also where the "urban heat island" exists. (not to mention storm water mitigation, air quality improvement and aesthetic value)

•  Foot per foot over equal time periods the emission reduction/avoidance is probably greater from a solar roof when you consider how that energy might otherwise be produced in the current social environment. (see next bullet) On the other hand theoretically this energy can also be produced elsewhere or by other renewable means whereas the flora that is able to grow on a living roof in a city would otherwise have nowhere to grow.

• So many little factors are involved that you really need to consider how optimal your location is for either or both. If your in a sunny rural area (with high energy prices)solar may be the way to go. If your in a predominantly cloudy urban setting then your a great candidate for certain living roofs. One thing to consider is that if your just going to be using much of that solar energy on extra power for air conditioning or heating, then a living roof might be just as good in terms of 'cutting out the middle man' and naturally keeping your house a little cooler, and/or better insulated.

I hope this was helpful and as I am not an environmental engineer or scientist I have much to learn about this overall issue as well. Please don't hesitate to comment.

http://www.builditgreenconcepts.com

Thank you folks for bearing with me through my non-green building / modern design / house kit blog musings... (as much as people laughed at Vintage Hat Fridays!) the next few weeks will be focused on what you came here for to begin with:
The SIPs passive solar modern house kit construction!

Yesterday, we spent a beautiful day hanging out on... our foundation.
...Despite the whiny four year old.
As it was muddy, my first order of business when we return is washing all those dog prints off the concrete. Which will not be fun, as by then there will be walls and a roof overhead. Dag.

The Structural Insulated Panels arrive at 8:30 Monday morning.
Our contractor's crew is Amish, hence our documentation will be interesting as the Amish don't want to be in photographs. (Which we completely respect- I am actually *very* excited that our Amish neighbors are putting together our passive solar modern design house kit - and look forward to talking to them about what they thought of it!)

For those of you interested in the Amish, I thought I'd show you their super-cool tractor / forklift!

This is what they will be using to unload the SIPs when they arrive!
I learned from our contractor that November is Amish wedding month. Hopefully it will not disrupt our house kit construction schedule too much, but really, if it does, that's fine by me. I have loved learning about the Amish and their community through our interaction there; the more I read about their traditions and close community interaction, the more I appreciate them.

So... you will see a lot of things happening now on the outside, then it's on to the interior, with modern, environmentally friendly design. This includes reused materials, practical functionality, off grid net zero decisions in systems. More on that soon...
In the meantime, here's some pictures from a lovely day on the land!

We have added another energy efficient product to our line. I love things that work well with my SIPs but somethings work great in any structure. Introducing our Seisco Tankless Water Heaters.

Tankless water heaters use less energy by heating water on-demand.  With a storage tank the water is heated over and over again.  Tankless Water Heaters help you reclaim space, lower your electric bill, and provide endless hot water to your home or business. By eliminating your storage tank water heater you add space to your house or structure. This is increadably important for those of us who have decided to live in smaller homes. 

Whether filling your bath tub, having multiple showers running, washing clothes, or doing it all at the same time, tankless water heaters can supply hot water through out your building on-demand. Using this system saves in water costs and you don’t let cold water in your lines run down the drain (and now for my corny punch line...) and you don't let your money go down the drain.

Green Open House Tour: Green Retro-fit: Built in 1818 and renovated with a grant from the state, one home on the Green Open House Tour now features modern green building systems.

The NESEA (Northeast Sustainable Energy Association) is hosting an open house on Saturday, October 4, from 10 am to 4 pm. The organization has coordinated with home owners and facility managers to provide access to numerous green buildings. Visit the site to see if there is an open house in your area and drop in to ask questions and see the installations that make new and remodeled homes more energy efficient. Just click on the map search, enter your zip code, and click GO. You can also search for projects that involve a specific type of green feature, like a geothermal heat pump, grey-water collection, or LEED rating in the drop down menu at left. I’m going to visit a home built in 1818 in Andover, MA that exhibits grid-tied Photovoltaics, a geothermal heat pump, a tankless water heater, and an alternative fuel vehicle for daily use.

This post was submitted by ThinkDwell. Visit Our Blog.

Healthier Spray Foam Insulation: The Green Cocoon installer spraying foam insulation to enhance a building's energy efficiency. The Green Cocoon uses a spray foam that substitutes some carbon-producing ingredients with soy-based ones.

New mixtures for spray foam insulation successfully uses healthier ingredients in a construction staple that is already widely accepted as fairly green. Spray foam insulation has been applied in many types of building projects. Chosen primarily for its excellent insulating and sound-dampening qualities, spray foam is a big player in achieving LEED Points by reducing the demands for heating and cooling thus reducing energy consumption. The benefits of this product outweigh the negative points associated with spray foam, most notably the oil that is mixed with a foaming catalyst to produce it. Traditionally, spray foam is made with petrol-based oil, which, of course, is a large contributor of carbon. It is seemingly a necessary evil: not a 100% green option, but the best option available.

Heightening the competition in the green product arena foam producers are using “a soybean based polyol that can replace the conventional petroleum-based polyols [and] help the polyurethane industry become less dependent on imported mineral Crude oil” (http://www.biobasedtechnologies.com/). See my “simple duck” references below for definitions! The percentage of soybean-based substitution currently varies by manufacturer but could be upwards of twenty percent when combined with renewable and recycled materials.

This smart substitution method should act as a model for other companies that produce materials consumed by the construction industry. Investing in research and working towards higher standards of sustainability can only pay off in the end as more building projects demand the healthiest, most eco-friendly products from businesses that strive to uphold responsible practices.

“Simple Duck” terminology (as promised, which I needed in order to write about this):

What is a polyol?

A polyol is a sugar alcohol. Polyol molecules can be chained together using certain chemical procedures to produce polyesters. Soybean-based polyols have been used as a petrol-substitute to manufacture parts of farm vehicles like John Deere tractors. (Deere & Co.)

What does the polyurethane industry produce?

Varnish, skateboard/rollerblade wheels, furniture and car seat foam. Maybe these will be the next products to get a boost of green-esteem from the diverse soybean.

This post was submitted by ThinkDwell. Visit Our Blog.