GREEN TIP #19
MY NEW SOLAR HOME PART 5
Winter may seem a strange season to discuss cooling but spring is just next month!
The good news is that you have already accomplished much of the required work with your passave solar for heating; cooling is now just doing the opposite! From previous tips, we already have placed our home in the proper east/west axis within ten degrees of true south. We are already using insulation of R-22 to R-50 which will assist greatly in keeping heat from getting in during the daylight hours.
To start with, lets turn to one of the most basic and cost effective tools we can use, namely the humble light bulb. Using the available everywhere CFR light bulb, that simply fits into any standard fixture, we can reduce heat output by 90%. The newer LED bulbs will answer some environmental concerns as well. These bulbs are more expensive, though prices may come down as demand increases. Both types use less electricity. With these types of bulbs, we also maintain the same light intensity as incandescent high heat producing bulbs. Another step we can take is to make use of daylight wherever possible. Simply turn off the lights during the daylight hours!
In New Mexico especially, we should always avoid using skylights and two story glass as the solar energy can become too intense during the warm season. An easy solution is to shade these heat gathering elements. Again, we must be mindful that building overhangs and using blinds on the south and west facing sides of a home are especially useful.
Using cellular shades are also helpful as are solar screens and using lighter colors. While there is not much we can do if a home is improperly oriented, learning to use shades, solar screens, lighter colors, less heat producing lighting, and strategic window use,can help greatly with cooling.
Always remember that planting trees for shade has great benefit. To assist further, here is a good web resource: http://www.nmsea.org/Passive_Solar/Passive_Solar_Design.htm Plesae share any additional web resources you come across.
Another suggestion might be trees such as the Purple Robe Locust http://www.starkbros.com/products/landscape-trees/flowering-trees/purple-robe-locust?gclid=CLHuyc_bk64CFakbQgodiWndJg. They grow very fast here and are drought tolerant.
There is much more to cover here, so we will take up this subject again when the weather gets warmer!
GREEN TIP #18
MY NEW SOLAR HOME PART 4
As we get more into planning our home; remember that we always need to apply the policy of careful planning and keeping in mind that we need to follow building codes and carefully check refrences of anyone we hire. This site: http://www.reedconstructiondata.com/building-codes/new-mexico/
is a good refrence guide for building codes. I use New Mexico here; but the site has information for other states as well.
For most of us; we are probibly going to hire a contractor. We should always bear in mind that the more we can educate ourselves, the better and more informed decisions we can make.
A few more tips worth bearing in mind are:
1-water absorbes and holds more solar energy but disipates it faster then masonry.
2-every element in a home resists thermal energy to a certain degree. The materials used efffect thermal efficency.
3-just as real estate in general; that old saying about location, location, location could be appplied to thermal efficency by saying: insulate,insulate, insulate!
4-an R value of R-22 to R-50 is prefered by most designers; even more In really cold climates.
While on that subject; we should consider our own climate as well. Here in New Mexico; while we may not have the warmest winters like parts of California or Arizona or the coolest summers like Montana or Colorado, we do have abundant shunshine, low humidity, and an overall mild climate. Our mesa land, for example, is perfect for constructing our energy efficient home. We have ample land and fewer building restrictions then other areas.
We have paid a lot of attention to thermal heating. Would we if this were posted in July? While we make use of passive heating; passive cooling is worth a look. Just as with warming; thermal mass plays an important role in cooling as well. In desert regions, materials like cob, rammed earth, and adobe make great choices. One of our community members has constructed an "earthship" designed home. This home is completly "off the grid". Several other community members have also built "off-grid" homes. I will feature these homes in the future. For now; keep researching. Next time will deal with passive cooling.
GREEN TIP #17
My NEW SOLAR HOME PART 3
Welcome to 2012! After our break for the holidays; lets resume working on our new solar home. When we left off; we saw that we want to pay attention to our placement of items such as windows and overhangs. We also see that the placement of trees and shrubs will also help with our overall plan.
Now, we will look at interior mass (partitions and tile etc.) vs. exterior mass (exterior walls and building materials) and how to take the most advantage of these attributes. Many passive solar home builders seek to deliver sunlight into the interior of the home where it can be absorbed by the structures internal mass. Items like tile and drywall also contribute to additional mass. "Envelope" insulation in the walls, floors, and foundation, etc help to preserve heat during the sunlight hours and gently distribute it at night and cloudy days.
Another factor to consider is what part of the internal mass is "free", like drywall, framing, lumber,furniture, etc.; and which part may be "Intentional" mass, an intentional part of our home's design. Items such as strategically placed brick, partition walls, concrete, tile, earthen materials, and other dense material can all be sutible; but it does need to be dense.
A through understanding of how heat moves and how thermal heat functions is essential and a few of the many websites on the sublect can help: http://evstudio.info/understanding-thermal-mass-in-a-passive-solar-design/
http://www.yourhome.gov.au/technical/fs49.html
http://homepower.com/article/?file=HP100_pg126_Letters_2
http://books.google.com/books/about/Passive_solar_house_basics.html?id=FAZ7FakYKukC
Remember, colors can also make a difference. The old concept was that thermal mass had to be dark is now being rethought. lighter colors can also be used. Thermal mass stores your heat: your overall design will help distribute it evenly. Good design will help this greatly. Another item to consider is that original idea of house placement for greatist solar exposure. Best bet; place your thermal mass in a direct path of the direct solar radiation! Keep studying and let me know your thoughts! See you next green tip.
GREEN TIP #16
MY NEW SOLAR HOME PART 2
In the last tip; we focused more on taking advantage of the sun's energy to warm. While it seems strange to speak of cooling in winter; spring and summer still occupy half of the year and will arrive soon! At this point, solar gain can be something we really need to be aware of.
We already know that we want to minimize windows on the north east and west sides of our home and make use of "low e" windows but we also want to be sure that we take full advantage of our special coating on the windows ability to retard heat gain or loss. These coatings help block the transmission of long wave length inferred radiation or heat. Properly placed, these windows can greatly help us maintain passive solar comfort . Manufacturers are now making designs that can greatly assist in building our solar home.
Overhangs help with the south facing windows but are generally ineffective on the east or west sides because of the low angles of the sun in early morning and late afternoon during the warm season. Here is when we again turn back to nature!
Trees are a great way to help. Plant them on the east and west sides to block that low angle sunlight. Also consider some vine covered arbors and ivy growing on the sides of the home. Canvas awnings, vertical louvers ,and blinds are also very effective at blocking solar gain on the east and west sides of our home in the warmer months.
We will continue with more tips next time. In the mean time, do your own research and email me your findings. It might make a good GREEN TIP!
GREEN TIP #15
MY NEW SOLAR HOME PART 1
In these next few tips; we will focus attention on creating our new solar home. Weather we plan a retrofit of our existing home, find a new home, or just build from scratch; we can all benefit from making informed decisions.
To be certain; living in the southwest is kind of like having our own private oil field! But; passive solar works in lower solar exposure areas and colder climates as well!The abundant sunshine, especially in New Mexico, is free and efficient. The only thing we need to be concerned with is positioning ourselves to take full advantage of the gift that nature is already providing.
In order to accomplish this, we will need to ask ourselves a few questions:
1-Does this site offer good and unobstructed solar exposure?
2- Is the existing home or building plans taking full advantage of passive solar by having the structure east/west axis oriented within 10 degrees east or west of true south?
3- Am I going to use the services of a professional solar designer or do it myself using a "solar pathfinder" device? http://www.solarpathfinder.com/video
4- Are or will the windows be mostly located on the south side of the home?
In the next GREEN TIP, we will look at items like "low e" windows and proper placement and use of items such as overhangs. The best news is that passive solar can work in cold northern areas as well!
SOME RESOURCES: http://www.builditsolar.com/Projects/SolarHomes/plansps.htm
http://www.youtube.com/watch?v=lzGaLw__kdk
GREEN TIP #14
FOSSIL POWER OR PEOPLE POWER?
So often, when we are choosing our next home, we always ask the most important question last. We should really always ask first "can I walk or bike from home to there?" This applies to work, shopping, and school. The more we can rely on "people power", instead of fossil fuels, the better our finances and environment will be.
To be certain; we can not always live in an urban area where all destinations are a walk, bike, or bus away, but we can still make distance to our main destinations a top priority. We can act as responsable consumers and demand that our communities have adequate public transportation and bike trails. Developers should be encouraged to build in well supported areas offering close proximity to businesses, schools, and shopping. Consumers need to demand it!
After all, it wasnt all that long ago (within many of our lifetimes) we had 1 car and no giant centralized malls at all! What did we do? We walked. We shopped at the local market, walked or rode the bus to school, and we used the car only when necessary. Every consumer, when house hunting, should always ask (even if it is only to plant a bug in the developers or agent's ear) if our prospective neighborhood has nearby public transportation, bike trails, and a good local business community. Was this sub division made using the new concept of urban infill? These questions and ideas need to become part of our national conversation. Remember; it only takes one to get the ball rolling. How about you?
GREEN TIP #13:
START A NEW GREEN INITIAVE!
OK...lets start doing something now. In one of my on-line publications; there is a link to publicize our own green initiatives. I have created a GREEN TIP BLOG PAGE for us to communicate our ideas on the subject. What are some suggestions you can think of, not just for our mesa land, but for your own home town as well? Please let me know. A few of my ideas for our mesa are:
COMMUNITY SOLAR PLANT
A CLEAN MESA COMMITTEE
A NEW SMALL SUSTAINABLE HOME COMMITTEE
We, as a group, can work with public and private sectors to acquire funding. We may even be able to acquire public funds for starters. Are you a planner? Community activist? Builder? This is a great time to get started. The rewards are many!
