As renewable energy continues to carve out a bigger stake in markets across North America, it often straddles the line between new ideas and accepted practices. While large developments push the needle closer toward a path of sustainability, it’s often the projects taking uncharted roads that allow us to envision our energy future. Below is a look at projects in the solar, wind, hydro, biomass and geothermal industries that are helping to reshape how we do business.

Solar

The ubiquitous utility pole stands proudly as an example of a necessary, yet perhaps unsightly, addition to the modern world. When they were going up, there may have been some groans. But, really, do we even notice them anymore?

Petra Solar is attempting to go the way of the utility pole in an effort to ingrain renewable energy into neighborhoods across its home state of New Jersey. And it’s doing this by jumping onto the back of those poles, quite literally.

The five-year-old solar company is behind a 40-MW project being installed for PSE&G, the largest utility in New Jersey. There are no solar farms or sprawling rooftop installations, but rather individual 220-watt modules mounted 15 feet up on utility poles across a wide swath of the state.

In all, PSE&G is installing between 180,000 and 200,000 units — one pole at a time — in the 300 towns and cities that the utility serves. The individual modules each feed directly into the grid, and they act as independent units. Together through Petra Solar’s software and monitoring network, they form a virtual power plant.

If a system of the same size were ground-mounted in a field, it would take up 300 acres, and vast amounts of time and money for siting, permitting, zoning and interconnection costs.

“It’s an ambitious effort, said Joe Deluca, Vice President of Development and Product Marketing for Petra Solar. “We’re on a nationwide and worldwide trek to make it common. We believe some day it may be odd to drive into a neighborhood and not see solar on utility poles and rooftops.”

Wind

A product of the 1970s, the building that houses Mount Wachusett Community College in Gardner, Mass., was born during a national energy crisis. At that time, the desire to break from a dependence on foreign oil led the school to build an all-electric campus.

Decades later, energy once again became the focus of discussion at the Central Massachusetts campus, only this time it was the cost as much as the source. With electricity bills approaching $800,000 annually, school officials decided that they needed to reinvent the institution as one focused on renewable energy.

First came the biomass heating system. Then, a 100-kilowatt (kW) solar array was installed on the roof. The big change, though, came earlier this spring when the school welcomed two wind turbines that will power 97 percent of the school.

The turbines have a capacity of 3.3 MW, and they’ve helped the school cut its electricity consumption from as high as 9 million kilowatt-hours (kWh) a year to about 5 million. Future energy efficiency gains could push consumption down to a target of 4 million kWh each year. If that becomes the case, the school will then be producing more energy than it is consuming. That could be quite a lesson — and cost savings — for institutions of higher learning and those who pay to go there.

“We’re one of the few campuses in the country, and perhaps the world, that is approaching zero net energy and zero net carbon – and that’s without buying green energy from another source,” said Ed Terceiro, a former school official who helped lead the wind turbine project.

Biomass

On a sprawling farm in Southwestern Iowa, it’s business as usual as row upon row of corn gets processed into ethanol. But there’s something different going on, and even those at the highest ranks of agriculture think this could be, if not the answer, perhaps an answer.

In its public relations battle, ethanol has a carbon problem. It’s widely debated how much carbon is emitted during the production of ethanol, what is certain is that the debate continues, and it’s not a good thing for the industry.

To find a solution, Tim Burns took a different look at the problem. Rather than viewing the carbon that is emitted during the ethanol refining process as a headache, he saw it as a business opportunity. That’s because he’s in the algae business, and algae love to feast on carbon. So on this particular farm in Shenendoah, Iowa, every day is Thanksgiving, at least from the perspective of the algae.

Burns leads BioProcess Algae, which has teamed with Green Plains Renewable Energy, for the world’s first co-located algae-ethanol plant. The carbon emitted during the fermentation process feeds the algae. For every unit of algal biomass produced, two units of CO 2 are absorbed into the growth process, which happens in giant vertical and horizontal reactors exposed to sunlight. The algae is dried and used to feed, not a car via biofuel, but livestock via feed. Burns is interested in making his algae-based business profitable, and right now that’s through creating feed. Eventually, as profits build, there will be room for a large-scale operation, the hope is that using algae to create biofuels will then become feasible and profitable.

Right now, the operation has moved into its second phase. And it was such a big deal, that U.S. Agriculture Secretary Tom Vilsack was there to give the keynote at the dedication this spring. The best line of the day came from Vilsack: “This is a remarkable project … I don’t understand it totally, but it’s really neat to look at.”

Geothermal

For an industry that has seen one new plant come online since the end of 2009, much of the difficulty can be attributed to the cost associated with exploration and permitting. But some of it also speaks to the unpredictability of a geothermal resource 20 years down the road. How can a developer promise how much power will be produced decades from now when negotiating a power purchase agreement?

Well, what’s more predictable than the sun? That’s not expected to go anywhere for a few billion years. Enel Green Power North America just might be onto something with the company’s decision to co-locate a 24-MW PV solar farm on a 240-acre parcel adjacent to its 60-MW Stillwater geothermal plant in Churchill County, Nevada. Conceivably, solar could offset concerns about resource predictability while contributing to a plant’s capacity.

The solar power produced will integrate into the existing plant, allowing it to produce more power, especially during periods of peak energy. It also saves the power producer the costs associated with interconnection and operation. This is the first such project in the United States, and according to company officials, likely the first in the world. Construction is ongoing, and the company hopes to bring it online by the end of the year. The questions will now focus on how to take advantage of this technological marriage beyond this one PV addition. Will there be a natural marriage between geothermal and concentrating solar power? Will solar see geothermal as an answer to its intermittency problem, and will geothermal turn to solar to make it more bankable?

Hydro

Free Flow Power has conventional hydro projects in every corner of the U.S., but the company’s most unconventional approach lies deep below the Mississippi River.

Since June, a jet engine-like hydrokinetic turbine has been generating power in what the company hopes will be a new wave of development. The company is still a ways away from turning this isolated project into viable option for utilities. But the implications are striking.

While wind turbines are at the mercy of weather patterns, underwater turbines are powered by steady river flows, meaning utilities could depend on them for their predictability. Clusters of turbines could also be located close to urban areas, where the power is needed and the grid infrastructure already exists.

According to some reports, the much higher density of water means that an average 5 mph flow in the Mississippi would be a force equivalent to 130 mph winds. Environmental review is an obvious consideration, and Free Flow is awaiting permits at dozens of sites along the Mississippi.

In the meantime, the company will continue with its test site near New Orleans, where the 40-kW capacity turbine turns the river’s power into energy. The company has said that it wants to install about 120 units per turbine farm, allowing each site to approach 5 MW of capacity.

Utility poles across many communities in New Jersey now include individual solar panels that create a virtual 40-megawatt power plant. Courtesy of Petra Solar The Central Massachusetts campus of Mount Wachusett Community College includes two wind turbines that provide 97 percent of the school’s electricity. Courtesy Mount Wachusett Community College An artist rendering shows what the algae-ethanol plant will look like after expansion. The algae reactors are currently housed indoors at the first algae-ethanol plant located in Shenendoah, Iowa. Photos courtesy Green Plains Renewable Energy The Stillwater geothermal plant in Churchill County Nevada is undergoing a facelift with the addition of 24 MW of solar panels in the first co-located geothermal-solar project in the United States. Courtesy of Enel Green Power North America In a pilot project, an underwater turbine that will generate power from currents has been placed in the Mississippi River. Courtesy Free Flow Power