Hydrocarbons have been flowing from the blown-out Macondo well since April. The Obama administration responded to the disaster by instituting a moratorium on deepwater drilling, though a judge recently struck down the ban. When we spoke with Tim Guinness, the London-based manager of Guinness Atkinson Global Energy (GAGEX), the moratorium was freshly minted and a major topic of conversation. Although that situation has changed, Guinness’ unique take on the spill’s impact and the future of the US energy sector remains valid.

How will the spill in the Gulf of Mexico affect oil prices?

Let’s start with the world’s oil supply. Much of the 40 million barrels a day of growth in non-OPEC [Organization of Petroleum Exporting Countries] output has come from deepwater activity, primarily in Brazil,West Africa and the Gulf of Mexico.

If the US and other governments’ reactions to the spill substantially increase the cost of deepwater exploration and production—South Africa has indicated it will significantly slow the development of offshore resources —the level of non-OPEC production would shrink. Currently, non-OPEC supply isn’t growing at all; rather, deepwater production expanded at the expense of shallow-water and onshore output.

We’ve long been in the camp that non-OPEC supply was due for a decline; with OPEC delivering more of the world’s supply, this process will accelerate.

This trend will translate into higher oil prices. Increasing the world’s reliance on OPEC for oil ensures the member nations receive a good price for their oil. On the whole, OPEC has played a fairly sensible game over the last 10 years and appears to realize that extraordinarily high crude prices aren’t necessarily good for business.

For better or worse, this increases the likelihood that oil will trade at $70 to $85 a barrel over the next three years, before slowly edging higher.

Will other governments crack down on deepwater drilling activity?

The impact will vary widely.

Norway, for example, has already announced that it won’t permit any deepwater drilling in the upcoming 21st licensing round until more information is available on what transpired in the Gulf of Mexico.

On the other hand, I expect the governments of Angola and Equatorial Guinea to react less severely— though I could be wrong. The logic is simple: These nations and other developing economies depend on royalties from oil production and are unlikely to enact drastic measures that would threaten this important revenue stream.

At the margin, I expect more oil to come from less-stable parts of the world.

Is a moratorium on deepwater drilling a sustainable policy over the long term?

Regulators could decide to slow offshore production, though that would be a mad decision. An extended ban would damage US oil and gas companies significantly and would be bad news for employment in Texas and Louisiana.

I feel terribly sorry for Louisiana, as the state suffered a painful double whammy: Not only did the oil spill wallop the tourism and fishing industries, but the subsequent drilling moratorium also hit businesses that support offshore oil and gas operations.

At the same time, unemployment in Louisiana has decreased because of the cleanup operations.

But the moratorium damages a number of fine US businesses at a point in the economic cycle when the economy is recovering from a deep recession—not the best time to crack down on an important growth industry.

On a positive note, the disaster and moratorium could prompt the US to improve energy security by expanding the use of natural gas in transportation or encouraging the adoption of electric cars.

Such a transition would increase energy costs; this is a case of slowly, slowly, catchy monkey. President Obama’s decision to stand on his head about oil drilling in the deepwater Gulf of Mexico is risky business.

Which companies stand to benefit from the situation in the Gulf of Mexico?

The problems in the Gulf of Mexico are probably good news for non-US service companies that have a strong presence in the Middle East. Kentz Corp (London: KENZ), for example, does a great deal of business in OPEC countries and should do well.

And because questions remain about how the Gulf situation will play out, companies with exposure to the region are more difficult to value; in stock market terms, names such as PetroChina (Hong Kong: 0857, NYSE: PTR) and Petrobras Energia (NYSE: PZE) should attract additional interest from investors. Tullow Oil (London: TLW) is another name that offers exposure to emerging markets.

I also expect outfits that operate in Canada’s oil sands to do well. We had a big position in some of these names four or five years ago and have gradually taken profits. We’re definitely not lightening our exposure now.

The best opportunity is in US natural gas. Prices for the commodity remain low, but the market is rebalancing slowly.

We’ve been adding to our exposure to US natural gas for about a year and expect the problems in the Gulf to help this calculated bet. There’s real traction behind the move to generate more electricity from natural gas and improve energy security in the US.

Over the past five years, fracturing and horizontal drilling have evolved to a point where significant amounts of natural gas can be extracted from shale deposits. It takes roughly six times longer to drill a horizontal well than a vertical well, but this approach yields 10 times the gas and offers attractive economics.

These developments have transformed North American natural gas from a sunset industry to a sunrise industry with a 30- to 200-year life ahead of it. For a while it appeared as though many of these companies would struggle to replace their reserves; now these outfits will be around much longer.

And the stocks aren’t too expensive. We like Newfield Exploration (NYSE: NFX), Chesapeake Energy Corp (NYSE: CHK) and Forest Oil Corp (NYSE: FST).

How easy would it be for the US to increase the profile of natural gas within its energy mix?

It will be a knotty process and won’t happen overnight.

If the government shutters future development in the deepwater Gulf of Mexico, the US likely would need an extra 1 million barrels of oil per day by 2013.

Obtaining this extra oil wouldn’t be a challenge, though these supplies would come from a less secure place and would cost more. But the government wouldn’t have a crisis on its hands.

If energy security is a priority, the US has an abundance of natural gas that could serve as a replacement fuel. Policymakers don’t need to decide right away whether electric- or natural gas-powered vehicles are the way to go. The best approach is to encourage the development of a few options and see how the economics look.

I also run Guinness Atkinson Alternative Energy (GAAEX). Our modeling didn’t forecast that electric cars would make a huge dent in the US market before 2020; we still expect the US to consume more oil in 2020 than it does today.

It’s impossible for the US to stop consuming 14 million barrels of oil for transportation in just a few years. That’s at least a 30-year goal.

The bottom line is that there’s a growing awareness about the country’s huge natural gas reserves and a lack of viable alternatives. I won’t pretend to know what policies the US should put in place to encourage the use of natural gas—you should probably talk to T. Boone Pickens about that—but these changes are coming.

What’s your best piece of advice for investors?

I would draw investors’ attention to two facts: Our portfolio has a price-to-earnings multiple of 10.7, and consensus estimates project that this ratio will decline to 8.5 percent next year. That’s remarkable in a world where energy prices are low but are poised to climb.

And don’t ignore the alternative energy space. Our alternative energy fund has performed atrociously, but its time is coming. The space will be booming in 2013; now is the time to invest.