The State of New Mexico now has a total renewable generation capacity that is over 1 million kilowatts. This huge milestone for renewable energy in New Mexico would have not been realized so soon without the NM Renewable Energy Production Tax Credit (REPTC). The REPTC is not just a credit on taxes owed, it is a refundable credit and can be allocated at any time to a new owner of renewable electric generation. The program supports utility-scale wind, biomass, and solar projects by providing a refundable corporate income tax credit for companies that generate electricity from renewable energy resources.

For wind and biomass, the credit is applicable on the first 400,000 MWh of electricity in each of 10 consecutive taxable years. There is a 1 cent per kilowatt-hour (kWh) credit for wind or biomass, and between 1.5–4 cents per kWh for solar generation. For solar, the credit is applicable only to the first 200,000 MWh of electricity in each taxable year. To qualify, an energy generator must have a capacity of at least 1 MW and be installed before January 2018.

This innovative program involved collaboration between utilities, industry, and state government. It has resulted in long-term economic and societal benefits, leveraged private investment, and increased renewable energy deployment.

Making a Change to Renewables Easier

The Energy Conservation and Management Division (ECMD) of the State of New Mexico’s Energy, Minerals and Natural Resources Department develops and implements effective clean energy programs—renewable energy, energy efficiency, alternative fuels, and safe transportation of radioactive waste—to promote environmental and economic sustainability and to protect public health and safety for New Mexico’s citizens. In 2003, ECMD began implementing the REPTC with several distinct initiatives and a long-term strategy.

Quantifying the potential for renewable energy: The ECMD began this effort by developing “investment grade” wind maps for the state using an international firm whose reputation was acceptable to investment bankers. With this data, wind developers and investors became more comfortable in developing projects. Projects were advanced by at least three years because developers had reliable data at an early stage with which to base decisions.

The additional New Mexico 10-year production tax credit made wind and solar attractive investments. Since the inception of REPTC, 10 wind and 21 solar projects have been completed, leading to 2,246,000 MWh in annual energy production. There are now 794 MW of wind and 232 MW of solar operating in New Mexico. These projects created approximately $2 billion in construction activity over the past ten years. A waiting list for the tax credit includes another 677 MW of wind and 65.5 MW of solar.

Helping Utilities to Meet the RPS: The existence of REPTC has also made it easier for electric utilities in the state to cost-effectively meet the targets in the state’s Renewable Portfolio Standard (RPS). Senate Bill 418 was signed into law in March 2007 and added new requirements to the states RPS. Under the new law, regulated electric utilities must have renewables meet 15 percent of the electricity needs by 2015, and 20 percent by 2020. Rural cooperatives must have renewable energy account for 5 percent of their electricity needs by 2015, increasing to 10 percent by 2020. Renewable energy can come from new hydropower facilitates, from fuel cells that are not fossil-fueled, and from biomass, solar, wind, and geothermal resources. The REPTC has assisted utilities in meeting this standard by providing a fiscal incentive. Since October 2007, the REPTC has been a refundable tax credit and can be allocated at any time to a new owner of the renewable energy generation project.

Revenue generated by land leases: Utility-scale renewable energy projects have become a steady source of revenue for the State Land Office. The New Mexico State Land Trust receives direct revenue from leasing public lands to wind, solar, and geothermal power plants. The projects qualify for the tax credit for ten years, but continue to produce renewable energy far beyond the 10-year incentive, as state land leases are commonly up to 30 years in length. Projected lease revenue for the next 38 years from renewable energy and transmission projects is projected to be $574 million.

Renewable energy projects are also leasing private land. This has become an important supplemental income source for a number of ranchers. Land leases, construction jobs and permanent maintenance positions are additional ways that renewable energy farms are supporting rural communities. A wind turbine typically generates about $20,000 in annual income to farmers and ranchers. PV systems also generate income to the land owners.

A Net Economic Benefit

For wind and biomass, the credit is $0.01 per kilowatt hour (kWh) and applies to up to 400,000 MWh for each certified generator in each of ten consecutive tax years. The statewide cap of the credit for wind and biomass is 2,000,000 MWh of production per year. For solar, the credit ranges between $0.015 and $0.04 per kWh (an average of $0.027/kWh) and applies to the first 200,000 MWh for each certified generator in ten consecutive tax years. The statewide cap of the credit for solar is 500,000 MWh.

Maximum tax liability for the state each year for the wind/biomass and solar tax credits combined is $33,500,000. In contrast, as noted above, the revenue for the next 38 years from renewable energy and transmission projects for state-owned land leases is projected to be $574 million, which spread relatively equally over that time frame will be $15 million per year, and will continue for an estimated 28 years beyond the 10-year tax incentive.

Without this tax incentive New Mexico would possibly have a small amount of wind energy, but it would in no way been able to create the substantial land lease revenue it has now with many, large-scale wind farms throughout the state. Creating the REPTC was New Mexico’s planned approach to make the state RPS acceptable to all stakeholders. In turn, this tax incentive leveraged private investment to benefit New Mexico. Since the REPTC was instated in 2003, several other states have examined the NM REPTC as a model for creating their own programs.

Highlights

• The Renewable Energy Production Tax Credit Program has brought wind and solar developers to invest in New Mexico, leveraging state investments. Interest has grown to the point that the state now has a project waiting list and legislators are considering increasing the cap on the annual energy production available for this credit.
• As a result of the program, 794 MW of wind capacity and 232 MW of solar capacity have been installed, representing just the beginning of clean energy development in New Mexico.
• The long-term benefits of the incentive program far outweigh the costs of the ten-year incentive program, resulting in continued economic benefits from and investments in renewable energy in the state.

Learn More about this Program

The New Mexico Renewable Energy Tax Credit Program was one of eight recipients of the 2014 State Leadership in Clean Energy Awards, an initiative of the Clean Energy States Alliance (CESA) to highlight exemplary state and municipal programs that advance clean energy markets. (See my previous blog from November 24, 2014.) CESA will be hosting a webinar featuring this program on December 8^th. The webinar is free to attend, but registration is required. You can learn more and register here.

«The use of waste heat for power production would allow additional electricity generation without any added consumption of fossil fuels,» said Bruce E. Logan, Evan Pugh Professor and Kappe Professor of Environmental Engineering. «Thermally regenerative batteries are a carbon-neutral way to store and convert waste heat into electricity with potentially lower cost than solid-state devices.»

Low-grade waste heat is an artifact of many energy-generating methods. In automobiles, waste heat generated in winter is diverted to run the vehicle heating system, but in the summer, that same waste heat must be dissipated to the environment. Coal, nuclear and other power plants require high heat to produce electricity, but after producing electricity the excess waste heat is routed to cooling towers to dissipate. Many industrial sites, geothermal sources or solar generating plants also create low-grade heat that is wasted.

The researchers want to take this waste heat and capture it to produce more power. Other researchers have tried a variety of methods, but most produce too little power to be workable, or they cannot provide a continuous resource. Logan and his team are using a thermally regenerated ammonia-based battery that consists of copper electrodes with ammonia added only to the anolyte — the electrolyte surrounding the anode.

«The battery will run until the reaction uses up the ammonia needed for complex formation in the electrolyte near the anode or depletes the copper ions in the electrolyte near the cathode,» said Fang Zhang, postdoctoral fellow in environmental engineering. «Then the reaction stops.»

This type of battery would be useless as a constant source of electricity if the reaction were not regenerative. Using low-grade waste heat from an outside source, the researchers distill ammonia from the effluent left in the battery anolyte and then recharge it into the original cathode chamber of the battery.

The chamber with the ammonia now becomes the anode chamber and copper is re-deposited on the electrode in the other chamber, now the cathode, but formerly the anode. The researchers switch ammonia back and forth between the two chambers, maintaining the amount of copper on the electrodes.

«Here we present a highly efficient, inexpensive and scalable ammonia-based thermally regenerative battery where electrical current is produced from the formation of copper ammonia complex,» the researchers report in the current issue of Energy and Environmental Science. They note that the ammonia liquid stream can convert the thermal energy to electrical energy in the battery. «When needed, the battery can be discharged so that the stored chemical energy is effectively converted to electrical power.»

One of the problems with previous methods was that the amount of energy produced in, for example, a system using salty and less salty water to generate electricity, was too small relative to the amount of water used. The thermally regenerative ammonia battery system can convert about 29 percent of the chemical energy in the battery to electricity and can be greatly improved with future optimization.

The researchers produced a power density of about 60 watts per square meter over multiple cycles, which is six to 10 times higher than the power density produced by other liquid-based thermal-electric energy conversion systems. The researchers note that the current thermally regenerative ammonia battery is not optimized, so that tinkering with the battery could both produce more power and reduce the cost of operating the batteries.

The researchers were able to increase power density by increasing the number of batteries, so that this method is scalable to something that might be commercially attractive.

Peidong Yang, Bin Liu and colleagues note that harnessing sunlight to split water and harvest hydrogen is one of the most intriguing ways to achieve clean energy. Automakers have started introducing hydrogen fuel cell vehicles, which only emit water when driven. But making hydrogen, which mostly comes from natural gas, requires electricity from conventional carbon dioxide-emitting power plants. Producing hydrogen at low cost from water using the clean energy from the sun would make this form of energy, which could also power homes and businesses, far more environmentally friendly. Building on a decade of work in this area, Yang’s team has taken one more step toward this goal.

The researchers took a page from the paper industry, using one of its processes to make a flat mesh out of light-absorbing semiconductor nanowires that, when immersed in water and exposed to sunlight, produces hydrogen gas. The scientists say that the technique could allow their technology to be scaled up at low cost. Although boosting efficiency remains a challenge, their approach — unlike other artificial leaf systems — is free-standing and doesn’t require any additional wires or other external devices that would add to the environmental footprint.

The authors acknowledge funding from the U.S. Department of Energy and the Singapore-Berkeley Research Initiative for Sustainable Energy.

The work, which appears in the November 27, 2014, edition of Science Express, points to new avenues for producing single-site supported gold catalysts that could produce high-grade hydrogen for cleaner energy use in fuel-cell powered devices, including vehicles.

«In the face of precious metals scarcity and exorbitant fuel-processing costs, these systems are promising in the search for sustainable global energy solutions,» says senior author Maria Flytzani-Stephanopoulos, the Robert and Marcy Haber Endowed Professor in Energy Sustainability and professor in the Department of Chemical and Biological Engineering at Tufts.

Flytzani-Stephanopoulos’s research group has been active in designing catalysts requiring a lower amount of precious metals to generate high-grade hydrogen for use in fuel cells. The water-gas shift reaction, in which carbon monoxide is removed from the fuel gas stream by reacting with water to produce carbon dioxide and hydrogen, is a key step in the process. Catalysts, such as metal oxide supported precious metals like platinum and gold, are used to lower the reaction temperature and increase the production of hydrogen.

The Tufts group was the first to demonstrate that atomically dispersed gold or platinum on supports, such as cerium oxide, are the active sites for the water-gas shift reaction. Metal nanoparticles are «spectator species» for this reaction.

Flytzani-Stephanopoulos says the new research suggests single precious metal atoms stabilized with alkali ions may be the only important catalyst sites for other catalytic reactions. «If the other particles are truly ‘spectator species’, they are therefore unnecessary. Future catalyst production should then focus on avoiding particle formation altogether and instead be prepared solely with atomic dispersion on various supports,» says Flytzani-Stephanopoulos.

The just published research describes how single gold atoms dispersed on non-reactive supports based on silica materials can be stabilized with alkali ions. As long as the gold atoms, or cations, are stabilized in a single-site form configuration, irrespective of the type of support, the precious metal will be stable and operate for many hours at a range of practical temperatures.

«This novel atomic-scale catalyst configuration achieves the maximum efficiency and utilization of the gold,» says Flytzani-Stephanopoulos, who directs the Tufts Nano Catalysis and Energy Laboratory. «Our work showed that these single-site gold cations were active for the low-temperature water-gas shift reaction and stable in operation at temperatures as high as 200°C.»

«Armed with this new understanding, practitioners will be able to design catalysts using just the necessary amount of the precious metals like gold and platinum, dramatically cutting down the catalyst cost in fuels and chemicals production processes,» she adds.

In many electrical devices, lithium-ion and metal-hydride batteries are applied for energy storage. Scientists are also studying alternatives to these established battery systems in order to enhance the safety, cost efficiency, sustainability, and performance of future devices. It is their objective to replace lithium by other elements. For this purpose, all battery components have to be newly developed and understanding of electrochemical processes is required.

Magnesium-based battery cells are presently considered an attractive option to replace lithium in batteries. In principle, magnesium allows higher storage densities to be reached than lithium. Other advantages of magnesium are its high abundance in nature, its non-toxicity, and its low degradation in air in contrast to lithium. So far, progress achieved in this area has been limited. For the design of magnesium batteries of high storage capacity and power density, suitable electrolytes are needed that can be easily to produced, that are stable, and can be used in high concentrations in different solvents.

At the HIU, a research team headed by Maximilian Fichtner and Zhirong Zhao-Karger has now presented a new promising electrolyte, which might allow for the development of an entirely new generation of batteries. The new electrolyte is characterized by a number of promising properties. It possesses an unprecedented electrochemical stability window and a very high efficiency. In addition, the electrolyte can be used in various solvents and at high concentrations. Moreover, the electrolyte is chemically compatible with a sulfur cathode, which can be discharged at a voltage close to the theoretical value.

Another advantage is the very simple production of the electrolyte. «Two commercially available standard chemicals, a magnesium amide and aluminium chloride, are applied. They are added to the solvent desired and subjected to stirring. This simple mixture can then be used directly as an electrolyte in the battery.,» Maximilian Fichtner says.