Although winter is finally over, it is still somewhat cold outside and we have to turn on the heat. Recently I’ve found a very interesting product which can be used by anyone to heat their home or apartment for free. Even if you rent, you can do it without getting the land lord involved. The only things you’ll need are the south-facing windows and a thermal mass solar window.

As you can see from the image above this windows measure 72 degrees F, while outside temperature that day was 22 degrees, with a 27 F high. (Historic weather data).

The 50 degree difference in temperature is the free heat that enters your home and stays. Here is how the Solar Thermal Mass windows work: In a nut shell, it as a 2 inches thick air and water-tight container filled with special liquid that collects and stores solar thermal energy. Special chemicals added to the liquid prevent stain deposits on the inner walls if the unit. In the picture above, these units are used as building blocks, and cover almost half of the south-facing wall.

In the winter, when the sun is low, these solar thermal mass windows collect solar heat since the sun hits them directly. In the summer, the sun is much higher and with appropriate shading, these thermal mass windows keep the home well insulated without collecting any heat. Additionally, a special low emittance and high solar gain argon filled window unit is installed just outside the thermal windows, so they are not directly exposed to the outside temperature.

How to heat your existing how for free

The picture above was taken in a new construction house, but for most people the interesting question is how to use these thermal mass windows in the existing home or apartment?

My plan was simple: I have 6 large windows that face south and an unheated balcony which cannot be used in the winter because it is too cold there. In the heated living space, we have new double pane Low-E windows installed, which are much more efficient than the original single-pane wood windows from the 50′s. I am going to build an enclosure in which I can stack 4-6 thermal mass solar window units, and have them up in the window during the winter months, and take them out in the summer.

This will not be as efficient as the one in the new construction home above but it will certainly help reduce my heating bill and carbon footprint.

As for the balcony, I first need to replace all the single-pane glazing and then I can stack the thermal mass windows all along the bottom of the windows. I’ll build special shelves to make the process of putting them up for the winter, and removing them in the summer, easier.

Traditional Sash Windows – Thermal Performance Solution

Here is how to make your traditional sash windows more energy efficient…

Sash Windows

Traditional vertical sliding sash windows, are based on a simple design of two of sliding glass panels (top and bottom sashes) and have been part of the UK’s architectural heritage for over three hundred years. The sash window originates from 17th century England, where the first prototype, the single hung sash window, was created by Robert Hooke, an inventor specialized, among others, in mechanics and architecture. The first type was more basic than those created nowadays and can still be seen in some historic buildings, predominantly of aristocratic ownership.

Solutions

Instead of replacing traditional sash windows, there are multiple reasons why owners should opt for restoring them to their initial appearance and at the same time optimize their thermal performance.

Traditional Sash Window

Sash Window Repair

The restoration process is ideally to be carried out by specialized companies and is always adapted to the specific type of sash windows and its particular deficiencies. Common sash window repair works include, replacing sections of the box frame normally the lower section of pulley stiles, lower sections of outer linings, bottom rails and window sills and replacing missing puttying and repainting. Using traditional carpentry and joinery methods with advanced modern epoxy resins ensures a permanent repair. This process does not alter their original appearance but instead, mends the alterations brought to it by time and natural phenomena.

Sash Window Draught proofing

This is also very effective process if done correctly it maximizes heat retention in the home and minimizes heat and energy loss. Sash window draught proofing is less known perhaps, yet once a sash window has been overhauled and draught correctly, even old sash windows can equal modern ones in terms of energy efficiency.

In this process the staff beads and parting beads are replaced with new beadings with a draught proofing material permanently machined into the beads, top and bottom sash re-fitted and also fitted with a draught proofing material (usually a brush pile). The 4no sash cords are replaced and the counter balance weights are re-

Sash Window Draught proofing

weight to the correct counter balance ensuring the sash close with a minimum gap.

Resources:

Find more green Home Improvement Ideas at Green Home Ideas blog.

It was a great Columbus Day weekend in Washington DC, and Solar Decathlon was making waves on the news… Well, actually it did not. Not even bigger green sites and blogs covered this truly green event. Probably there were much more important things happening in our capital – like Obama’s newly “adopted” dogs .

So I’ll let the big guys do their things, while I tell you about the event, which so many people waited 2+ years for, and worked so hard to make it happen – ladies and gentlemen – Solar Decathlon 2009!

This was our first Solar Decathlon, but certainly not the last. Since we were sponsors of Team Boston Solar Home, most of my coverage will be focused on it. However, there were many great solar homes this year: Team California and Team Germany were battling for first place (you can see Team Germany solar home in the picture above – a black house, second from the right).

As I wondered through the Mall, looking at these homes and being hesitant to stand in line to see very similar interior set-ups, my main focus was on the outside. Solar technologies, energy efficiency and exterior design were my main concern, as these factors make a true solar home, while the inside can always be remodeled.

Team Boston Solar Home:

As a future architecture student, and a “construction worker” now, I look at these houses with a slightly different perspective than most people. For me, the ease of construction, most energy efficiency and reasonable cost are the most important things, followed by a nice design. Unfortunately, many of the innovative approaches used for this competition, are not accessible to the masses, and remain to be a privilege for the most extravagant home buyers with deep pockets. While I have no problem with it in general, in my opinion, the purpose of a Solar Decathlon is to move innovative green building technologies into the mass housing market, so that such technologies would actually make a major difference in improving the environment and reducing CO2 emissions.

It is expected of all these homes to be super insulated and have solar PV panels on their roof. I was interested in innovative new approaches at achieving maximum effect (energy efficiency or energy generation) using the least expensive methods. In this regard, the Boston Solar home has (had) great potential, if not for the massive glass array on the northern side of the house. All these windows and doors will let all the heat escape in the winter, which makes it that much less efficient. This is a fixable situation however – just remove most windows and put a wall there

Despite potential heat loss, the liquid-filled glass units on the southern side of the house will collect tremendous amounts of solar heat and store it, making it much easier to heat this house. Find out more about these liquid-filled solar thermal windows and wall panels.

In addition to solar thermal wall panels, Boston solar home has about 6.4 KW solar pv system on the roof and a solar thermal hot water heater, for heating and domestic use. There are many other new and innovative design features used by BAC (Boston Architecture College) and Tufts University students in the construction of this home – too many to list here. You may check out the project’s website – www.livecurio.us.

Team Spain solar home:

Another solar homes that attracted my attention was the one build by Team Spain (which for some reason was doing VERY poorly in this competition).

Apparently, these bi-pv cells are very good at capturing indirect sunlight and help the house generate the most electricity it possibly can.

Team Spain used a very interesting )in my opinion) approach at capturing ALL available solar energy with their powerful solar PV array. This roof mounted array can rotate at the center, following the sun going across the sky, thus always keeping the most efficient angle of the PV panel to the sun. It is basically a gigantic solar tracking system, which is however complicated and expensive systems to implement, which make this house not as competitive in terms of costs and ease of building.

Additionally, the glass walls of this home have integrated solar PV cells, which captures even more solar energy. It is a good idea, but and overkill in my opinion, and the roof mounted solar system should be more than sufficient and, unless they used “dummy” cells on east, west and north sides of the house, it is a waste of solar capacity, as the sun will barely or never hit those solar cells.

Cornell University Solar Home:

Another interesting design, which for some reason reminded me of the Water World movie was a solar home built by Cornell University students. It featured three round “rooms” connected to each other, and a large solar PV system, which for some reason was mounted flat to the ground.

It may not be the best designed house (in terms of competition rankings), and round rooms make it ever more difficult to build, but the steel frame and a VERY cool vintage design made it very attractive. As I was writing this, Cornell’s solar home was in 6th overall place, with a few more contests to go. You can view current team rankings here: http://www.solardecathlon.org/scoring/

As a side note, as of Oct. 13th, Team Boston solar home is in 12th position and Team Spain is in 18th place, while 1st place belongs to Team California.

Let the best solar house win!

The Solar Decathlon will continue for another week or so, and there are a lot of contests left in which either team can pull forward dramatically. Therefore, I will not even try to predict the winner. All houses presented in the Solar Village this year were very well designed and built, and the green building technologies used in them will in the (hopefully) near future migrate into traditional construction markets and help home and building owners reduce the over all energy use and make our environment better. This competition is also an inspiration for the new wave of architects who will be literally building our future homes and infrastructure, and as you can see, they all have great ideas. I will continue the cover the Solar Decathlon 2009 in future posts, and soon you will be able to review the IB flat roof installation which we did on the Curio Home – look forward to seeing it soon on our cool roofing blog.