In this image the large over-hanging branch coming up from the base of the tree is casting a lot of shade on the house, but it is a hazard and has a good chance of breaking off in high winds or ice storms. I would remove the branch to allow the stronger main crown to fill out and shade the house.
Even before electricity was invented and the luxury of air conditioning was developed,  trees, shrubs and vines were planted to keep homes cooler in the summer and warmer during the winter months.

If you want to shade your home from the summer heat as well as heat your home with the winter sun, it would be best to plant deciduous trees, shrubs or vines on the east, south or west side of your home. Use evergreen plants in your landscape if you are primarily trying to cool your home to cast shade year round. 

Strategically placed landscaping can reduce the temperature inside your home by 8-10 degrees F, annually saving an average of 30 percent on your electric bill.  Shading your air conditioning units without obstructing the air flow can reduce the temperature inside your home by an additional 3 degrees F.  Planting grass, ground cover, shrubs, vines and flowers to shade the ground also helps by keeping the soils cooler, thereby reducing the heat reflecting off of your walls and windows. 

I love the natural day light that comes in through the thirty windows in our house — all but three windows and one door are positioned correctly or shaded by trees to make our house more energy efficient. We have two majestic live oaks in the front yard that are on the south side of the house which shade our 2,800 square foot home almost all day on the east , south and west sides. I would hate to see our electric bill if we did not have trees providing shade for our windows, walls and roof. 
An added bonus of planting trees to help reduce energy consumption is the ability to enjoy their shade while being outside during the summer months. There can be an over 20 degree Fahrenheit difference between standing on a lawn in full sun or under a tree in the shade.  It is a fact  that you and your home will feel notably cooler in the shade of a landscape with trees and a solid lawn. 

Do your research and find out the best plants suited for your landscape. Use indigenous plants to Texas or the coastal area. These plants are already adapted to the harsher costal climate and will perform better with the least amount of care. Do not plant fast growing, trashy trees near your home like an Ash tree which will not hold up well in high winds. Plant trees far enough away from your home that the roots will not disturb your foundations, sidewalks, drives and leach lines.  In addition, make sure you maintain your trees so any fallen branches do not become a hazard. 

Don’t forget to maintain the foundation planting and lawn around your home, watering will help maintain the moisture content to prevent your home from shifting and keep the air temperature around your home cooler.