Can Solar Bring the Heat Big Industry Needs to Decarbonize?

There’s a pressing need to develop and make use of low-, preferably zero-carbon fuels to power industry in order to reduce greenhouse gas (GHG) emissions, realize climate change goals and avoid the worst effects of a rapidly changing climate. New, industrial solar thermal technology and systems that are cost-competitive with conventional, fossil-fueled counterparts exist today, but the market space is vast and diverse, billions of dollars of investment are required and, generally speaking, they haven’t attracted the attention they merit, according to industry players and analysts.

Energy-intensive industries in Europe can achieve net-zero emissions by mid-century, but with 2050 just one investment cycle away, time is running out, highlights Material Economics in a recent study. It could take decades before the current generation of fossil-fueled, industrial thermal energy technology and systems are replaced with clean energy assets. Moreover, cost-effective solar thermal systems that can power the highest-temperature industrial processes have yet to be developed.

That still leaves a broad and deep range of industrial processes that the latest solar thermal energy systems can fuel economically, however. “GlassPoint’s technology can cost-effectively provide heat and steam up to 550°C, which covers the majority of industry’s global heat demand. This includes a range of processes throughout the chemical, food and beverage, metals and mining, and fuel industries as well as desalination,” John O’Donnell, vice president of business development for GlassPoint Solar, an emerging leader in the field, told Solar Magazine.

Satisfying industry’s huge, insatiable demand for steam and heat

Manufacturing heavy industrial products, such as cement, steel and chemicals, requires tremendous amounts of high-temperature steam and heat. So does oil and gas and mineral resources extraction and production. Furthermore, a wide range of other industries—food processing and beverages production and textiles manufacturing, for example—require lots of steam and heat, as well. Fossil fuels are used to produce practically all of the thermal energy used in all these industries.

A whopping 74 percent of energy consumed by industry worldwide comes in the form of steam and heat produced primarily by fossil fuels , GlassPoint Solar CEO Steven Moss highlights in an article recently published in Scientific American. That results in lots of greenhouse gas (GHG) emissions, as well as other forms of environmental pollution.

Worldwide industry is responsible for about one-quarter of total emissions. Emissions from transportation and residential segments are trending down, but the International Energy Agency (IEA) projects that industrial emissions will increase by some 24% by 2050.

In Europe, heavy industry accounts for around 14% of GHG emissions. The corresponding figure in the U.S. is around 22%. Overall, emissions leveled off in China, the world’s largest source of emissions, for the three years 2014–2016. They rose 1.7% in 2017, and as of last December were projected to rise 4.7% year-over-year, however, according to the Global Carbon Project’s 2018 Global Carbon Budget.

U.S. carbon emissions rose sharply last year despite ongoing growth of renewable energy capacity and the retirement of coal-fired power plants . Emissions from industry surged 5.7 percent, more than in any other sector, including transportation and power generation, according to a preliminary estimate from the Rhodium Group, Moss points out in his article.

Innovative solar thermal technologies exist that can replace fossil fuels to produce industrial steam and heat cost-effectively, but they’ve yet to prove themselves across the wide, diverse range of industrial processes. Moreover, the issue of reducing emissions associated with industrial processes hasn’t gained the attention it merits among policymakers, according to Moss.

“‘The industrial sector is still almost entirely ignored,’ despite increased efforts from policymakers and the business to tackle emissions...We must turn our attention to industry—the sleeping giant of climate action,” Moss wrote.

Process heat is an overlooked opportunity to slash GHG emissions, and solar technologies operating at the scale needed by industry are currently available. It’s time to embrace them and stop industrial heat from heating up our planet.

The grand challenge of decarbonizing industrial energy use

Decarbonizing energy use in industrial and manufacturing processes figures among the biggest challenges associated with achieving renewable energy, greenhouse gas emissions reduction and climate change goals, according to Thomas Koch Blank, an engineer and a principal in the Rocky Mountain Institute’s (RMI) industrial practice.

“I know that concentrated solar projects with thermal storage [for electricity] have penciled out at some very low prices in certain locations, and I can imagine that direct steam production can be an attractive option in the near term in certain regions, such as parts of Australia, Chile and the Middle East, where standalone solar energy is already being produced for as low as USD0.02 per kilowatt-hour (kWh),” Koch Blank told Solar Magazine.

“My understanding is that solar thermal has not really taken off at scale yet to replace large boilers largely due to storage challenges. Industrial companies need to run facilities at capacity when the sun’s not shining, and energy resources such as solar are not as ‘dispatchable’. It’s not necessarily a cost-per-kilowatt issue, rather the ability to control energy output. What do you do if you have a scheduled or unscheduled process break and the boiler is going full steam at noon? Well, you can vent the steam so as not to over-pressurize the system, or you have to have some storage capacity.”

Available solar resources and access to energy infrastructure play large roles in determining the economic feasibility of industrial use of solar steam and heat, Koch Blank explained. Industrial and heavy manufacturing plants tend to be clustered in hubs where there’s ready, reliable access to lots in the way of energy resources and supporting infrastructure.

The economics of industrial energy use is changing amid ongoing growth of distributed solar, other renewable energy and advanced energy storage technologies, however, he highlighted. “Low-cost renewables can really reshape global industry and emissions footprints...Given cheap renewable energy costs, we’re anticipating a global trend in which the competitive landscape for energy-intensive industry is going to change. For example, an iron ore miner that has been exporting its ore to China to produce steel may see no reason to continue shipping but rather take advantage of solar energy and storage to manufacture steel in Australia,” Koch-Blank said.

GlassPoint Solar’s enclosed solar trough technology

“In a solar thermal system, mirrors focus sunlight to intensify its heat and produce steam at the high temperatures needed for industry. Another key advantage is the ability to store the heat using simple, proven thermal energy storage in order to deliver steam 24 hours a day, just like a conventional fossil fuel plant,” Moss explains.

With the right technology, solar thermal can be a reliable, efficient and low-cost energy source for industrial steam generation.

Enclosed in specially-designed, custom-built greenhouses, the specially designed mirrors GlassPoint uses to concentrate the heat of sunlight track the sun throughout the day. That heat is focused on pipes filled with water, which then boils and produces steam.

GlassPoint’s enclosed trough solar thermal technology concentrates solar radiation over 100 times and can provide cost-effective, zero-carbon heat across most of industry’s required temperature range, according to O’Donnell. “A portion of industry’s heat demand is in the low-temperature range, which can also be serviced by flat plate and other non-concentrating solar collectors,” he added. “These systems have typically been used for smaller installations for low-temperature applications, such as heating water to 90°C for laundries and textile processing.”

Some industries, such as glass or cement production, require very high-temperature heat or steam, typically in the 800–1,000°C range. Commercial solar thermal technology capable of meeting this need doesn’t exist at present, O’Donnell continued. “There are substantial challenges here that are currently being researched, including by the US DOE SunShot program, which is exploring advanced materials capable of handling high temperatures,” however, he pointed out.

Steam and heat for industry delivered on-demand, 24x7

GlassPoint’s industrial solar thermal systems deliver heat that is “dispatchable,” aka on-demand, 24x7, O’Donnell says. “[It] is well-proven and in operation at very large scale around the world. Many solar thermal power stations now generate electricity around the clock by storing energy collected during the day as heat, in tanks of molten salt. Decades of research and experience have led to this low-cost, safe, durable form of energy storage. Today it costs less than 20% as much to store energy as heat in molten salt than to store energy as electricity in batteries,”  he highlighted.

Different industrial companies require steam or heat at different temperatures and according to different delivery schedules, O’Donnell noted. “We work with customers to deliver solutions customized for their particular needs,” he said.

GlassPoint’s technology resolves other key challenges associated with development of concentrating solar thermal technology: Minimizing the physical footprint of concentrating solar thermal technology so as to fit easily into the limited space typically available inside industrial plants and shielding it from the harsh environmental conditions found there or on remote sites where extreme weather conditions exist, such as mines and oil and gas fields.

“The tight packing and higher efficiency of enclosed trough systems cuts the land needed for solar industrial heat in half,” O’Donnell said. “With these large reductions in cost and land use, solar energy becomes practical and cost-effective in a wide range of locations and processes. We see the market for solar energy in industry growing by a very large factor as a result.”

In addition, “unlike solar electricity projects, which can be sited far away on cheap land in ideal conditions and transport energy long distances to end-users, solar steam and heat for industrial processes must be generated at the industrial site. This means that efficient use of limited and expensive land immediately adjacent to facilities—factories, mines and oilfields—is a key element of a practical, cost-effective solar installation.”

Reducing the recurring costs of operations and maintenance

Then there are the long-term, recurring costs of operations and maintenance. That can be particularly challenging in harsh industrial or remote environments. “The costs of frequent cleaning necessary to maintain performance [particularly in dusty areas] have been a barrier to the wider deployment of solar thermal energy in industry,” O’Donnell said.

GlassPoint’s solar steam generators are equipped with automated washing robots that are based on designs by the global greenhouse industry over many decades, O’Donnell continued. “The robot washes the greenhouse roof fully automatically with water recovery, eliminating the impact of dust and replacing labor-intensive manual cleaning processes that would not be possible in many remote industrial areas.”

With some funding from the U.S. Dept. of Energy’s SunShot Initiative, Sunvapor is working with industrial companies to replace fossil-fueled thermal energy technology with those fueled by emissions-free renewable energy. The company worked with Horizon Nut to build a 50-kW solar thermal installation at a pistachio processing facility in California’s Central Valley. The project partners also joined forces to expand solar steam production for food industry processes, such as pasteurization, drying and roasting, Moss points out.

GlassPoint, for its part, is developing and operating some of the largest industrial solar thermal systems. Ironically, oil and gas companies number among the early adopters of solar thermal technology. Oman’s largest oil producer is using GlassPoint’s concentrated solar trough technology to produce steam and extract oil underground.

GlassPoint’s Miraah plant in Oman can produce 660 metric tons of steam every day, and should exceed 1 gigawatt (GW) of solar thermal power when completed, according to the company. The same technology is being deployed in California to reduce emissions from one of the U.S.’ oldest and largest oilfield.

Factors driving demand for solar steam and heat for industry

Cost savings, not surprisingly, are one of two main factors driving adoption of solar steam in industry, O’Donnell said. “In many industries, energy supply is one of the lead operating costs, and energy strategy is fundamental to a company’s profits. In many sunny regions of the world, GlassPoint can deliver the lowest cost source of energy, lowering production costs and improving profitability.”

Efforts on the part of industrial companies to achieve sustainability goals is the second factor driving adoption of solar steam in industry, O’Donnell continued. “Increasingly, products made more sustainably, with a lower carbon footprint, command market share and premium prices. There are many pathways to achieve emissions savings, but the heat used to power production operations is one of the largest contributors to emissions throughout a product’s life cycle. By replacing large amounts of fuel-fired heat with zero-carbon heat, GlassPoint’s solution is a big hammer—we offer one of the largest opportunities to reduce total emissions throughout the supply chain,” he said.

“Regions with the highest annual direct sunshine will have the best economics for using solar heat or steam. Many industrial hubs have developed in these high sunshine areas, known as the world’s sunbelt,” O’Donnell explained. “These areas are also experiencing strong population and economic growth, where energy is in high demand and often imported from other countries, leading to increasingly high energy costs. These factors make solar the most competitive fuel choice for industrial companies looking to reduce production costs and deliver more sustainable products.”

Some leading industrial adopters of solar thermal can be found in Europe, Koch Blank pointed out. “There’s plenty happening in Eur [in terms of industrial decarbonization] because of carbon pricing. Some big areas where we see good traction are electrification of boilers.”

“I think that’s largely the factor of high natural gas and reasonably low electricity prices,” Koch Blank said. Europe, in general, doesn’t rate very highly in terms of solar energy resource, which constrains the use of solar thermal or electricity production, he noted.

That said, some leading European industrial companies are forging ahead and investing in solar thermal technology and systems. Austria’s Voestalpine and Hybrit, a Swedish steel manufacturer, are both piloting hydrogen-based, zero-carbon processes for steel manufacturing, Koch Blank highlighted.

On the other side of the globe, “Australia is really putting its foot forward, and a lot of political and financial capital into building a hydrogen-based economy, especially for the western region.” Australia’s efforts extend to developing hydrogen fuels for shipping and aviation. “That’s an exciting push for the decarbonizing industry, as well,” according to Koch Blank.

Based on the economics, industrial solar thermal systems hold promise in steel-producing countries with limited access to domestic supplies of oil, gas or coal, Koch Blank continued. Those include Japan, South Korea and Singapore, which are “all exposed to liquefied natural gas (LNG) prices in the USD12–20 per million BTU range,” he explained. “That’s a lot higher than domestic U.S. prices. They don’t have coal and they’re importing all, or nearly all, their energy, so unless they have nuclear energy, they need to find alternatives.” comment↓