If you think that global growth trends and technological advancements make the energy sector one to keep an eye on, you may be very interested in this list.

On the sector level, there are usually hundreds if not thousands of stocks to sift through. Worldwide, there are more than 2,400 energy stocks; on the three major U.S. exchanges, there are more than 300 energy stocks. One way to pinpoint more interesting companies is by looking at company insider buying trends.

Company insiders such as upper management and members of the company's board know more about their companies than any other investors. When they believe in their company enough to buy shares, it's a solid signal of confidence in the company's outlook.

We screened all energy stocks trading on U.S. exchanges for those seeing significant net insider buying over the last six months.

Do you agree with these insiders on their bullish company outlooks?

Use this list as a starting point for your own analysis.

List sorted by net insider purchases as a percent of share float. (Click here to access free, interactive tools to analyze these ideas.)

1. Vantage Drilling (NYSE: VTG): Provides offshore contract drilling services to large multinational oil and natural gas companies, government-owned oil and natural gas companies, and independent oil and natural gas producers in the United States and internationally. Market cap of $348.79M. Net insider shares purchased over the last six months at 5.35M, which is 3.22% of the company's 165.97M share float.

2. Star Gas Partners (NYSE: SGU): Operates as a home heating oil distributor and services provider in the United States. Market cap of $335.26M. Net insider shares purchased over the last six months at 1.20M, which is 2.56% of the company's 46.85M share float.

3. PHI (Nasdaq: PHII): Provides helicopter transportation services to the integrated energy, and independent exploration and production companies primarily in the Gulf of Mexico. Market cap of $321.51M. Net insider shares purchased over the last six months at 200,000, which is 2.30% of the company's 8.69M share float.

4. Energy Partners (NYSE: EPL): Operates as an independent oil and natural gas exploration and production company in the United States. Market cap of $556.92M. Net insider shares purchased over the last six months at 200,000, which is 0.70% of the company's 28.72M share float.

5. Global Partners (NYSE: GLP): Engages in the wholesale and commercial distribution of refined petroleum products and natural gas, and provides ancillary services in the United States and internationally. Market cap of $360.39M. Net insider shares purchased over the last six months at 37.40K, which is 0.54% of the company's 6.93M share float.

6. SandRidge Energy (NYSE: SD): Operates as an independent natural gas and oil company in the United States. Market cap of $2.79B. Net insider shares purchased over the last six months at 1.37M, which is 0.40% of the company's 346.20M share float. This is a risky stock that is significantly more volatile than the overall market (beta = 2.05).

7. QR Energy (NYSE: QRE): Engages in the acquisition, production, and development of onshore crude oil and natural gas properties in the United States. Market cap of $753.97M. Net insider shares purchased over the last six months at 63.30K, which is 0.37% of the company's 16.96M share float.

8. Rex Energy: Operates as an independent oil and gas company in the Appalachian, Illinois, and Denver-Julesburg basins. Market cap of $606.03M. Net insider shares purchased over the last six months at 77.33K, which is 0.22% of the company's 34.99M share float.

9. NuStar GP Holdings: Owns general partner and limited partner interests in NuStar Energy that engages in the terminalling and storage of petroleum products, transportation of petroleum products and anhydrous ammonia, and marketing of asphalt and fuels. Market cap of $1.30B. Net insider shares purchased over the last six months at 74.27K, which is 0.21% of the company's 34.80M share float.

Interactive Chart: Press Play to compare changes in analyst ratings over the last two years for the stocks mentioned above. Analyst ratings sourced from Zacks Investment Research.