What's New with Renewables?
Manufacturers and consultants discuss how renewable power technologies—solar, wind, microturbines and fuel cells—are progressing, and how these technologies are faring in the marketplace. CONSULTING-SPECIFYING ENGINEER: It seems that the biggest barrier to renewable energy sources has been first cost.
Manufacturers and consultants discuss how renewable power technologies—solar, wind, microturbines and fuel cells—are progressing, and how these technologies are faring in the marketplace.
CONSULTING-SPECIFYING ENGINEER: It seems that the biggest barrier to renewable energy sources has been first cost. Are costs coming down?
AHUJA: It's still an issue, even though energy awareness is increasing. About every other project, we look at renewables as an alternative. And 75% of the time, it is well received by the design team. But in the end, it is taken out due to the budget. Also, with constantly evolving technology, there is no one winner or proven system with a long history of maintenance-free performance.
LEYDEN: It's true that first cost has been a barrier, especially with solar electric systems. However, solar prices have come down tenfold in the last 15 years, with continuing cost reduction every year. Consequently, solar electric systems are delivering an increasingly rapid return on investment. The technology has no fuel cost, little maintenance and can continue operating for more than 30 years.
And the solar industry is extremely focused on further reducing cost to make photovoltaics more competitive with fossil fuels. PV also offers health and environmental benefits, a high quality of power and a reduction in the strain on the utility grid, especially at peak demand times in the summer when PV is producing its peak power.
FIELD: On the microturbine front, cost has come down somewhat since it was first introduced in 1998. In the most common size ranges—30 kW to 300 kW—microturbine costs are comparable to similar-sized, continuous reciprocating engine solutions. Microturbines are far less costly and more available than other renewable alternatives.
DUNCAN: We've watched output costs from utility-scale wind projects decline from more than $250 per megawatt-hour (MWh) in the early 1980s, to $4 to $5 per MWh today. This makes it competitive with natural gas. Solar PV costs have also declined sharply, but from a higher base, to a current level of around $250 per MWh. We fully expect the cost declines for both resources to continue, with solar overtaking wind as the most cost-effective renewable resource within 10 to 15 years. A greater ability to capture economies of scale at manufacturing, the ability to site PV nearly anywhere and the ability to integrate panels into building features and facades will all be factors. Solar costs could decline even more rapidly with government incentives and purchases to accelerate production.
CSE: Speaking of government incentives, has the U.S. government's support of renewable energy increased in any significant way?
LEYDEN: The federal government's support of solar has been anemic, with little or no increase in recent years. Budgets for PV, which are already small, continue to be targeted for reduction, when the exact opposite should be occurring—especially in light of the country's dependence on foreign energy supplies in these times of global instability.
DUNCAN: Government support has declined sharply under the current administration, for everything from budget dollars for research and development to consistency in tax policies that undergird renewable project and technological development.
AHUJA: I disagree somewhat. New government grants for renewable energy have neither increased nor decreased in the past couple years. What's happening is that competition for grants has increased. Most of the time, grant support—along with environmental and efficiency benefits—justifies the inclusion of these technologies in a project.
FIELD: The Feds are fostering renewables in their push for energy efficiency in government buildings, part of which includes the use of on-site combined heat and power (CHP) systems. The administration's energy bill also has some level of support applicable to the use of biogas as fuel for power/heat generation. We would, of course, like to see a greater effort to encourage the use of biogas-to-energy projects. The overwhelmingly common practice of simply venting or flaring off this gas is an amazing waste. With CHP, instead of using electricity to ignite and burn off these gases, one can create electricity from them.
CSE: What, if anything, is happening at the state level?
FIELD: Oddly enough, individual states are ahead of the federal curve on this. In California, for example, there is a state mandate that utilities must pay 40% of the total project cost of every qualifying sub-megawatt biogas-to-energy project as soon as that system goes online. And conventionally fueled CHP systems qualify for a 30% rebate.
CSE: On the subject of outside influences, what effect has the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) certification program had on renewable energy sources?
AHUJA: LEED has encouraged the use of renewables and provided buildings with a nationally-recognized standard on environmental and efficiency achievements. Offering LEED certification as educational credentials also encourages LEED professionals to pursue the use of renewables on their projects.
LEYDEN: We've certainly found that many architects and building owners are now specifying solar for their buildings as a way to lower operating costs and earn LEED points.
DUNCAN: I have to disagree. I think that LEED has thus far had only a marginal effect on expanding reliance on renewables. Most of the emphasis in LEED is on materials, while the energy criteria have been somewhat complicated to understand. On-site solar PV is probably discouraged by the high level of reliance on renewables required to earn a LEED point.
In fact, interest in green buildings has probably done more to stimulate interest in other commercial sectors, such as natural foods and ski areas.
CSE: What promising advances are being made these days in the most common renewable technologies?
AHUJA: One advancement is the incorporation of renewable sources into basic building elements. Another is the ability to connect all renewable power sources—wind, solar and biogas—on a common power base.
As for new technologies, aero-turbine wind-power sources can be used in metropolitan areas where real estate is not available for large-span, noisy propeller windmills. Also, renewable sources such as biogas can also be generated in small digesters for communities or buildings.
LEYDEN: PV efficiency has increased more than 25% in the last two years, and clever new ways of installing PV on rooftops have been developed.
FIELD: We're seeing a growing adoption of microturbine technology worldwide. While most deployments are conventionally-fueled CHP installations, about 10% of the 2,500 microturbines we've shipped to date are deployed to use renewable flare gases as fuel.
CSE: Is that a significant number?
FIELD: Users seem to be moving beyond the "kick-the-tires" phase for microturbines, and their adoption will continue to increase. Regardless of the fuel type, these systems are far more fuel efficient and far less polluting than utility plants. In CHP applications, microturbine fuel efficiencies of 80% or more are common, whereas utility power plants average only 33% fuel efficiency, according to the U.S. Dept. of Energy. And keep this in mind: the average utility-generated MWh produces about three lbs. of smog-forming NOx. Cutting just one MWh reduces that by 85% or more.
CSE: Has renewable energy's popularity in Europe made any impression on American building owners?
DUNCAN: I've seen no discernable impression from my perspective.
LEYDEN: I beg to differ. Photovoltaic systems, which are more common in Europe, offer solid examples of how PV can be integrated in building design. Also, the success of PV programs in Germany, and the accompanying increase in high-tech jobs, has caught the attention of many policymakers, especially on the state level. Good solar PV policy creates a significant number of jobs and has many system-wide benefits.
CSE: Electrical deregulation was expected to open a number of doors for distributed generation and other alternative on-site power technologies. But what has really happened? Has deregulation been a good thing or a bad thing?
DUNCAN: Deregulation was expected to broaden the energy markets, making more room for renewables. But in fact, the process has been so commodity-and price-driven that resources with significant first costs, such as conservation and renewables, have been disadvantaged. Now utilities laden with high-cost contracts entered into during the California deregulation meltdown have greater difficulties dealing with higher first-cost alternatives than before. On the other hand, natural gas price spikes have led some utilities to consider price-stable resources like wind. Other utilities have opted backwards to coal.
FIELD: One positive is that deregulation has made it far less difficult for private, public and municipal facilities to use DG technologies to improve reliability, control energy consumption and reduce emissions, while simultaneously cutting costs.
LEYDEN: I would add that deregulation has spurred new sources of financial support in several states, as public utility boards have set up solar programs funded by societal benefit charges on utility bills. Though marginally supported by the utilities prior to deregulation, these programs are much stronger under the new regulatory environment.
AHUJA: I don't think deregulation has affected the implementation of renewables simply on the basis that deregulation itself has not succeeded in some areas of the country. But given that, many states are taking a conscious step in that direction.
Tom Leyden , Vice President of East Coast Operations, Powerlight, Crosswicks, N.J.
Anil Ahuja, P.E. , Senior Vice President, CCJM Engineers, Chicago
Keith Field , Director of Communications, Capstone Turbine, Chatsworth, Calif.
Angus Duncan , President and CEO, Bonneville Environmental, Foundation, Portland, Ore.
Standardizing Fuel Cells
The principles behind fuel cells were first explored as early as 1839. But it wasn't until they were applied aboard America's Gemini and Apollo spacecraft that the technology saw widespread application.
Before the technology could be used broadly, pioneers realized potential safety issues had to be addressed. In 1990, AGA Laboratories—which now operates as CSA America—was asked to develop a standard for fuel cell products. In 1998, this document was adopted by ANSI. The organization later relinquished this standard to CSA America, and it is now known as CSAFC-1 Fuel Cell Power Systems.
Today, several additional national and international standards and codes have been published to guide fuel cell design, construction and other operational requirements. One of the most important factors to consider is that testing and certification organizations review a fuel cell's entire power system, including the reformer, the stack, the power conditioning system, the enclosure and the thermal management system.
Field evaluation services are available to help designers confirm that all components and connections meet applicable national, state and local codes.
Although they are the heart of a fuel cell power system, the cells themselves are just one of the many components that make up the system configured and installed on-site. Because fuel cell power systems differ in design and performance from traditional power plants, unique inspection expertise is required.
The attractiveness of fuel cell power continues to grow as energy-dependent commercial businesses, industrial plants and institutional facilities seek to reduce their reliance on conventional power supplied via regional electrical grids or traditional on-site power generation technologies.
Established standards for the design, safety and performance of fuel cells—and rigorous, third-party evaluation of fuel cell products and installations—enable system designers and engineers to confidently apply this technology and deliver the benefits of this alternative energy resource to their clients.
Todd Strothers, Manager, CSA International Charlotte, N.C.