Taking the laptop outdoors either in your own yard, the summer cottage, or in a park outside your office is a good idea.. kind of.
But you need to consider a couple of things.
Energy - how long your battery can provide you with power, without the laptop being plugged in to mains power. The energy consumption is very logical: the brighter display settings you use, the more devices you have plugged into the machine like mice, USB devices, digital camera cables, and so on - the more you spend, thus less time to work.
Moist - sometimes outdoor weather is pretty moist. This means a couple of things. You might feel a bit strange using the keyboard; and this happens also when your fingers are getting cold. Second, the machine might not like moist too much. Most laptops are okay with normal moisture ranges, but if there's a particularly warm and moist weather, or a lot of visible fog, don't take the laptop outside. It might get trashed or work erroneously.
Screen contrast - visibility. It's amazing how much irradiant light comes from the sun. In the office space or inside your home, it's usually dimmed by shades in the windows and so on. But outside, it's totally different thing. The sun's energy is defined like this (in Wikipedia):
Daylight or the light of day is the combination of all direct and indirect sunlight outdoors during the daytime (and perhaps twilight). This includes direct sunlight, diffuse sky radiation, and (often) both of these reflected from the Earth and terrestrial objects.