This is true. Unlike the previous energy star credits where the window ratings varied with what part of the country you lived in with the North having the most aggressive heat retention U Value and allowing heat gain through the windows into the house, to the south where the U value had less emphasis placed on it, and a more aggressive stance on gaining heat into the house through the windows also known as solar heat gain coefficient where the heat gain is a bad thing as far as energy consumption.
Under Obama's stimulus package they took a one size fits all stance where the want a pretty aggressive U value and a very aggressive Solar Heat Gain Coefficient which limit us in the North from absorbing heat through the windows in the winter to help our heating costs. What I have had customers do to help gain the credit is put the qualifying windows on the North and northwest sides of the house or where windows look out over a covered porch and do not help the house gain heat from the sun and they use windows that will allow the solar heat gain on the south and eastern side of the house where they get more sun during the winter days.
The credit is 30% of the cost of the windows and doors only (not labor for installation) up to $1500. If you do the math this amounts to $5000 worth of windows and doors so it can be pretty easy to max this credit out and a new entry door qualifies for the credit also

My husband and I live in Minnesota and are planning to replace the windows on the southwest side of the house we're remodeling with windows that qualify for the tax credit.
The Low-E coating on windows - and Argon gas between the panes - helps to reduce heat transfer through the glass, which keeps more heat out during the summer AND keeps more heat in during the winter. Low-E also blocks most UV rays, which can fade your interior.
These options have been recommended for variable climates. But if your house was designed to capture solar heat gain in the winter and to be protected from the sun in summer (ours is not), then you wouldn't want them.

Galefarm is absolutely correct. The qualifications for the tax credit are ridiculous. It was obviously written to mainly benefit those in Southern climates. The big issue those of us in the industry have with it is the SHGC. It has to be below .30. That's great for someone in Florida, Texas, Arizona etc but really bad for someone in Minneapols, Buffalo or even Chicago. Houses in Northern climates would benefit more from a window with a U-factor of say .32 as long as the SHGC is above .39. As Galefarm stated I would put the windows that you want to qualify for the ETC on the North side of the house to max out the $1500 tax credit and then go with as high a SHGC on the rest of the house. You will see almost no difference in heating and cooling costs with a window with a .32 U-factor as compared with a .30. But, there will be a more noticible difference in a window with a SHGC of say .22 when compared with one at .40 in terms of energy savings and comfort.

Government getting it wrong....not possible?!?!?

Wow,

Such cynicism from someone who lives and works in our nation's capital? ;-)

Rebhoward,

Some really good advice on here, and a great discussion, but I personally would never put a high solar gain window on the west side of a home unless there are provisions for blocking solar heat gain when needed.

In relatively mild winter weather the western sun can seriously overheat a west-facing room and in summer the cost of heat gain that you have to deal with can easily exceed the value of the solar heat gain in winter thru the same west-facing window.

For someone who lives in a heating dominated climate, high solar gain on south-facign windows can be a very good idea. High solar gain on west-facing, or to a little less extent, east facing, may not be such a good idea.

Maximum U-factor on north-facing windows is without a doubt a very good idea. I would also suggest that you consider the same high performance windows on east and west side as well.

And has been pointed out already, you can likely meet the maximum refund by going .3 / .3 on the other-than-south facing windows in your home. Leaving the advantage of higher solar heat gain on the southern-facing windows if that is what you want.