No doubt you've heard all about the U.S. becoming increasingly energy independent courtesy of the shale drilling boom. So, how do you make a buck off this energy business without undue risk?

You could try an energy producer like Enerplus Energy (NYSE:ERF). The company produces crude oil from the Bakken and natural gas from the Marcellus. Great assets with enough pipeline and rail takeaway capacity to get the product to market.

Enerplus stock has been on a roll, rising from about $15 a share a year ago to $23 a share today. Not bad considering earnings have been flat for the past five quarters and the monthly dividend hasn't done much better. A lot of optimism is built into the price of the stock; but what do you suppose will happen if earnings disappoint?

Invest in "picks and shovels"
A safer investment in the energy market is a company that supports the likes of Enerplus. For example, all drillers need equipment ranging from drill bits to heavy lifting equipment, and National Oilwell Varco (NYSE:NOV) supplies these and more to the energy exploration industry. This includes offshore and onshore drilling activities, domestic and foreign operations.

The company got its big break back in the 1990's when it became a supplier to hydraulic fracturing companies. At that time, no one else wanted the work and National Oilwell Varco stepped in. This niche play paid off. Since 2004, revenues have climbed 10-fold, net earnings 20-fold and cash 30-fold. The stock has gone from under $15 a share then to $77 a share today after adjusting for a 2:1 stock split in 2007. Today, the stock sells for under 14 times earnings, an attractive price given its business and earnings history.

What lies ahead for National Oilwell Varco? As a major (some would say dominant) provider of drilling equipment, the company is dependent on drilling activity. Offshore drilling in the Gulf of Mexico continues to rebound after the Deepwater Horizon disaster. Offshore drilling in the North Sea, Asia, and Russia is also slated to grow. U.S. hydraulic fracturing activity shows no sign of slowing down. All this portends continued growth for National Oilwell Varco and its investors.

While not as sophisticated as drill bits or lifting equipment, hydraulic fracturing requires proppants that keep fractures in rock open and allow oil or gas flowing to the surface. One popular proppant is sand, Northern White sand in particular, and Hi-Crush Limited Partners (OTC:HCRS.Q) owns a big pile of it -- by one estimate, 33 years' worth. With Enerplus and other drillers drilling more tightly spaced wells and using more frac sand per well, Hi-Crush sand looks like it will be in demand for years.

The stock has been on a tear for the last 12 months, more than doubling while the S&P 500 has increased about 20%. A look at the company's financials tells why. From mid-2012, when the company first went public as a master limited partnership, earnings have steadily grown from $0.33 a share to $0.49 a share in the most recent quarter. Consensus estimates are that the company will earn $0.92 a share by the end of 2014. Quarterly distributions have grown from $0.2375 a share to $0.52 a share. The current yield is about 4%.

Will these earnings and distributions trends continue? Hi-Crush management seems to think so. In its latest investor presentation, Hi-Crush projected frac sand consumption will steadily grow through 2017. The company reports its average contract life rose from 2.8 years at the end of 2013 to 4.0 years as of May, 2014. Helping the longevity of its contracts are extensions of contracts with Weatherford US Ltd, and US Well Services LLP. In response, Hi-Crush projects annual frac sand deliveries will increase from an originally estimated 2.5 million tons for 2014 to roughly 4 million tons and then 5 million to 6 million tons for 2015.

Final Foolish thoughts
For steady income growth and capital gains, I recommend Hi-Crush. The company has an essential raw material for hydraulic fracturing and I don't see consumption of frac sand declining anytime soon. Expansion projects focused on major shale plays should further strengthen the company's long-term prospects. The distributions look safe not only from the perspective of growing earnings, but also from the rock-solid distribution coverage ratio of 1.26. So long as hydraulic fracturing stays active in the US, Hi-Crush investors should do well.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.