Buy low, and sell high. In investing, as in life, we all hope for "a better tomorrow," and one in which the decisions we make today ultimately pay off -- figuratively and, in the case of stocks, literally, too.

And here's the really great thing about investing in stocks: At the same time as you invest money today in hopes of making more money in the future, you're also helping to finance the businesses that are working to make that future a better place to live in. Whether striving to cure disease, reduce dependence on fossil fuels, or free workers from drudgery and dangerous jobs, the stock market is full of promising companies that are working to create a better tomorrow. Here are three of them that our Foolish investors think might be worth a look: bluebird bio, Inc. (NASDAQ:BLUE), NextEra Energy (NYSE:NEE), and Fanuc Corporation (NASDAQOTH:FANUY)

Palm holding glowing digital globe

The future looks bright for these three stocks. Image source: Getty Images.

Jump into the future with this biotech

George Budwell (bluebird bio): While numerous biotech companies can claim that they're working on developing "transformative new medicines," the gene-therapy specialist bluebird bio is undoubtedly doing just that with its lentiviral vector platform, T-cell immunotherapy expertise, and gene-editing capabilities. Bluebird is at the cutting edge of a wave of novel gene-therapy platforms that seek to bring unprecedented treatments to market for both severe genetic diseases and cancer that can correct the underlying genetic cause of the disease, instead of simply addressing the symptoms. 

Turning to the specifics, Bluebird sports two late-stage clinical programs for its lead Lenti-D/LentiGlobin gene therapy candidates as treatments for a rare neurological disorder known as cerebral adrenoleukodystrophy, as well as a fatal blood disorder called transfusion-dependent beta-thalassemia. In addition, Bluebird previously signed a patent licensing deal with Novartis that gives it royalty rights to the newly approved chimeric antigen T-cell receptor therapy (CAR-T) Kymriah, and it also has a CAR-T development deal of its own in place with biotech heavyweight Celgene Corp. for patients with advanced multiple myeloma. As a result of its substantial clinical efforts, Bluebird is on track to have several game-changing gene therapy products on the market by as early as 2022. 

Perhaps what truly differentiates Bluebird, however, is its exceptionally strong balance sheet. Although most clinical-stage biotechs are poorly capitalized relative to their long-term cash needs, Bluebird exited the most recent quarter with a whopping $1.1 billion in cash, cash equivalents and marketable securities. That's more than enough to get Bluebird to its next-stage of maturation (regulatory filings), and perhaps even into the commercial portion of its lifecycle. 

The downside, though, is that Bluebird's stock is anything but cheap. Because of its top-notch gene-therapy platform and outstanding financial position, Bluebird is already trading at over 7 times its last stated cash position. That's not to say that this stately market cap isn't justified based on the company's long-term value proposition, but any clinical or regulatory missteps could result in a sizable pullback. As such, this futuristic gene therapy stock arguably isn't well suited for risk-averse investors.  

Invest in the future of energy

Neha Chamaria (NextEra Energy): When you think of a better tomorrow, you surely think of a cleaner environment. If so, owning a renewable-energy stock like NextEra Energy is a great idea. NextEra is the world's largest producer of wind and solar energy today, a business that it runs primarily through its subsidiary, NextEra Energy Resources (NER).

NextEra is targeting capital expenditures worth nearly$40 billion to $44 billion between 2017 and 2020, out of which $22 billion to $25 billion is expected to go to NER to expand its renewables portfolio that includes wind, solar, battery storage, and natural gas pipelines. Between 2017 and 2020, NER expects to have signed contracts for 10,100 to 16,500 megawatts (MW) of solar and wind energy.

Likewise, NextEra's other subsidiary and its primary utility division, Florida Power & Light Company (FPL) is also investing in renewables. FPL is aboutto bring 600 MW of solar capacity online by early next year and has lined up another 1,600 MW of solar capacity for development beyond 2018. FPL has several other clean-energy projects in the pipeline.

The best part is that with NextEra Energy, you're investing not just in a clean-energy company but also in a dividend growth stock. NextEra expects to grow its adjusted earnings per share by a compounded average rate of 6%-8% through 2020. Its dividends are likely to grow at a similar pace, going by the company's dividend track record.

The future is robots

Rich Smith(Fanuc Corporation): "Progress isn't made by early risers. It's made by lazy men trying to find easier ways to do something." It was Robert Heinlein, the dean of science fiction writing, who first wrote that, but as a lazy person I agree with him wholeheartedly -- and I just love the idea of building robots to do more of our work for us. 

Fanuc Corporation may not be my favorite robotics stock -- as I've said before, that's ABB Ltd. of Switzerland. But if you believe as I do that robots are the future, then you have to at least consider making an investment in Fanuc as well.

Why? Well not to put too fine a point on it, but as the world's leading manufacturer of industrial robots, and the fastest growing large company in this space to boot, Fanuc is currently "the company to beat" in robotics. Based out of Japan, Fanuc Corporation does about $5.5 billion in annual business selling robots and other industrial machinery. It makes a nice profit on this, too, earning $1.3 billion on robot sales  last year -- about a 24.4% net profit margin. And with a projected long-term annual earnings growth rate of nearly 13%, Fanuc is the fastest growing of the large robotics companies -- growing even faster than ABB.

Granted, with fat profit margins and a high growth rate, Fanuc stock doesn't come cheap. In fact, at 34 times trailing earnings, it's expensive. But like most companies, Fanuc's stock ebbs as well as flows. Should the price tomorrow become better than it is today, Fanuc stock is one I wouldn't mind owning myself. 

George Budwell has no position in any of the stocks mentioned. Neha Chamaria has no position in any of the stocks mentioned. Rich Smith has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Bluebird Bio. The Motley Fool has a disclosure policy.