Archive for the ‘Building Systems & Methods’ Category
VIDEO: What is a LEED Home? Watch!
Friday, November 13th, 2009
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Prefab Houses Bomb
Wednesday, July 1st, 2009Remember the big push for prefabs? There have been several iterations of the “Structural Insulated Panel” idea. Then there was the house delivered prebuilt on several trucks. All you had to do was plop it down on your foundation, hook up the utilities and sewer, and you were done.
Great idea, right? Well… Not so much. Despite the entrance of famed architect Daniel Libeskind into the prebuilt fray, Build LLC is declaring the whole prefab fling dead.
Read the whole article and their 10 reasons why: here.
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Understanding The Alternatives
Saturday, April 25th, 2009While there are plenty of inexpensive ways to save energy in homes and businesses, the coming of the Obama administration seems to have piqued interest in alternative power. Tax benefits and rebates from power companies are sprouting up all over the country.
In California, for instance, public utilities are required to purchase power back from customers. This is called a “grid-tie” system. Businesses sell all the power they generate to the power company and then buy their power back as per normal, ensure a steady flow of reliable electricity. If properly designed, the alternative generation system can be a money maker for the company. Consumers, on the other hand, get offsets for power generated. Generation surpluses are carried forward to offset future deficits. A properly designed system can reduce a home’s utility bill by 90% or more.
Financial incentives for alternative energy generation
Beyond just the straight reduction in utility bills, there are a number of programs available to help offset the cost of installing an alternative power system. While these programs are changing all the time, here’s a short list:
- Database of State Incentives for Renewables & Efficiency (DSIRE) is a “comprehensive source of information on state, local, utility, and selected federal incentives that promote renewable energy”: (www.dsireusa.org)
- U.S. Dept. of Agriculture’s 2002 Farm Bill Initiative—”Renewable Energy & Energy Efficiency Program” provides information on USDA grants “available for eligible agricultural producers and rural small businesses to purchase renewable energy systems and make energy improvements”: www.rurdev.usda.gov/rd/farmbill/9006resources.html
- California Energy Commission (CEC): Emerging Renewables Program Rebates: www.consumerenergycenter.org/erprebate/index.html
- NYSERDA Rebate Program: www.powernaturally.org/Programs/Wind/Installers_all.asp?i=8
- The Energy Trust of Oregon is an organization funded by “Public Purpose Funds” which supports Oregon renewable energy and energy efficiency projects through grants: www.energytrust.org/RR/wind/index.html
In California specifically there is also:
- The Net Metering program
- The Feed-In Tariff
- In San Bernardino County, the Green Building Incentive
- In Santa Monica, the Green Building Grant Program
- And the Self-Generation incentive Program
And Federally there are also the:
- Residential renewable Energy Tax Credit
- Business Energy Tax Credit
It’s Cool But Not Cheap
As with all things new and or in vogue, alternative energy is still not cheap. Well designed systems start at $10-$12 per watt and go up from there, depending on individual choices for generation systems, additional systems desired (such as battery backup or completely “off-grid” systems) and so on. Home owners can expect their new alternative power system to pay for itself in 10-15 years, depending on local utility costs.
A business system can take significantly longer depending on the size of the system and how it is used. This is because, in California anyway, businesses must sell their power to the utility company at wholesale rates, which is about half of what they pay to purchase that power back.
Solar
The best known alternative source of power is, of course solar. It’s the great granddaddy of alternative energy and has long been the darling of alternative energy enthusiasts. Things have changed since the early days of solar power. Now not only are the familiar crystalline panels more efficient than ever before, solar roofing systems are also available. Some of them don’t even look like solar panels!
As with all alternative power systems, there are many do-it-yourself kits out there for those who are handy. But the best systems are always professionally designed for the specific application and location.
Wind
Small scale wind power is the new kid on the block. As such, it’s poorly understood. Companies are sprouting up all over the place touting their product’s abilities, taking advantage of consumer ignorance.
Wind energy functions on a very simple principle of physics: The amount of wind a turbine can generate is equal to the cube of the wind speed. Therefore the holy grail of wind turbines is rotor size. (Laymen refer to the “rotor” as the “blades”.) The larger the rotor—or more accurately, the more surface area available to catch the wind—the less wind it takes to generate a given amount of power. It’s that simple. It’s also why commercial wind turbines are well over a hundred feet tall with rotors a hundred feet in diameter. The power company wants maximum power generation at the average (or “rated”) wind speed for the locale.
So don’t be fooled by manufacturers touting the energy output potential of their products. You’ll never hear an expert in wind energy talk about a turbine’s power “size”. What you’ll here them discuss—at length—is it’s rated power at its rated wind speed. In other words, how much power the turbine will produce at the speed the wind blows most of the time at that location.
Of course, there are many different ways to increase surface area on a turbine, and all seem work equally well.
Consider the turbine show at right. While the manufacturer didn’t have a spec sheet available at the time this was written, according to the faq, at a speed of 28 mph this turbine produces half its rated power of 10kw. And at 14 mph, it outputs 2kw. Not significantly lower than the 2.4kw produced by the more traditional tower shown above with it’s 12 foot rotor.
The Ideal System
Beauty, they say, is in the eye of the beholder. Likewise with alternative energy. Wind offers a viable (though no cheaper) alternative to solar power in some parts of the country. In many places, combining the two would provide all the energy needs of a home or business, making an off-grid option fully viable.
Personally, I think a combined wind/solar system with a grid-tie and a battery backup is the idea system. If the worst happens, the grid is still there, but by in large, the property is energy independent.
There’s no doubt in my mind that not only are are alternative energy sources here to stay, in another couple of decades they may well make up a significant portion of our national power grid! I sincerely hope so!
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VIDEO: The Cost/Benefit of a Green Roof
Saturday, November 1st, 2008Green Roofs. It’s an old technology that is becoming new again as cities and municipalities look for methods of reducing the operating costs of buildings and controlling rainwater runoff. The question is: Does it work, and it it worth it?
It can cost an enormous amount of money to install a green roof! In an existing building it is doubtful the roof system will support the weight of the soil, plants, and the water the roof will absorb. The entire structure would have to be reinforced before a green roof can be installed. Meaning that, as stated in the video below, installing a green roof on an existing high rise apartment building can cost as much as $100,000!
But, as the Wall Street Journal reports, the cost may be worth it.
Technorati Tags: green roof, green building, roofing, roofing systems
