Google makes some pretty awesome tools and one of the really useful ones which can be used to help plan more energy efficient buildings but doesn't seem to be all too well known yet is Google Sketchup. You can Download Sketchup for Windows XP/Vista and Mac OS X.

Sketchup is a 3 Dimensional drawing tool, it's easy to learn and use. Within a few hours of playing around you'll be able to have some pretty complex drawings happening.

One of the things I like the most about Sketchup is the ability to geo-reference your drawing. That means you can embed a location of where the drawing will be on the earth. It works very similar to the way you can now geo-tag your digital photos and videos.

The geo-referencing feature of Sketchup also allows you to place your 3D model into Google Earth - it's a really cool feature but it's not the part that makes it useful while you're in the planning stages of building a structure.

Planning your structure to use less energy for heating or cooling means that you're going to need to know how the sun hits your structure throughout the day at different times during the year. Sketchup and the geo-referencing feature allows you to easily visualize how the sun hits your structure, the way the sun will shine through the windows and the shadows your structure will produce at any time of day during the year.

There are two important details you have to give Sketchup to allow the program to give you an accurate rendering of the sun's effect on your structure.

Now would be a good time to click on the above thumbnail to get yourself familiar with the two dialog boxes in Sketchup that'll allow you to set up your drawing properly.

Let's look at the dialog box where I've highlighted the values for Geographic Location and Solar Orientation. You can bring this dialog box into focus in Sketchup by going to the menu items Window -> Model Info.

The Geographic Location entry is self-explanatory. Sketchup makes it easy by giving you the option of selecting your location from pull down menus. If you want to be more accurate and know the coordinates of where you're going to place you structure you can hit the Set Custom Location button and enter your own coordinates in the decimal degrees format.

We're doing all this so we can see how the sun interacts with our structure and Sketchup needs to know where the sun is in relation to our structure. Sketchup refers to this relationship as Solar Orientation and allows you to supply a value for it.

While it might sound a little complicated, you can be assured that Google made setting the Solar Orientation easy.

Make sure you have the Show in Model option selected. When this is turned on you'll notice an orange line across your drawing which is a little thicker than the other axis lines.

This orange line represents the Solar Orientation of your drawing and points to where you've told Sketchup North is. When you adjust the value of the Solar Orientation or North Angle in the dialog box the orange line will move so you can see what the different values will do.

As long as you know where north is in relationship to your structure and the general location of it, Sketchup will show you really accurate shadowing.

If you can't see your shadows, or you want to adjust the date and time or want to adjust how the shadows render, you can do this through the Shadow Settings found under Window -> Shadows.

Adjusting the time of day shows how the sun shines through the windows and the shadows your structure will create at the time of your choice.

Have fun with Sketchup. Use it to plan your structures and save money on heating or cooling costs which will reduce the energy footprint of your future building.