Caterpillar has arguably done more than most in the realm of corporate social responsibility over the many decades of its existence, in terms of bringing power to areas of the world that suffer from remoteness and relative impoverishment. Its latest offering builds on that legacy.

The US equipment manufacturing giant recently launched its hybrid microgrid at its proving grounds just outside Tuscon, Arizona and Decentralized Energy heard from its Electric Power division management about an offering that promises a great deal for the third world in particular.

“Africa doesn’t have time to wait 6-7 years to give these people power. If we don’t give these people power and (by extension) more access to the web for example it’s going to make it more and more difficult for them to catch up in development,” says Rob Schueffner, Microgrid Commerical Manager at Caterpillar’s Power division.

Management made much reference to the vast swathes of the Earth’s population that still do not have access to reliable electricity, or indeed any electricity at all. It’s a major motivation in developing the product, an adjustable blend of solar technology, storage and traditional generation, along with advanced monitoring and control systems.Caterpillar microgrid solar at Tinaja Hills

The qualities of the solution, namely scalability, ease of installation and cost-versatility, not to mention environmental suitability marks it out from the company’s traditional generation products and there is real belief in the transformative effect it can have on communities..

It can be used in applications that vary from telecommunications towers, industrial facilities, mining installations, to remote villages, islands and rural communities. It is designed to reduce fuel expenses, lower utility bills, decrease emissions, and reduce the total cost of ownership while increasing energy efficiency in even the most challenging environments.

One of Cat’s greatest attributes is its dealer network and the hybrid microgrid can be purchased as turnkey installations or design-to-order solutions. Ranging from 10 kW to 100 MW, units can be added in a modular fashion to create systems customized for a variety of power requirements.

Press attending the unveiling of the technology recently were shown it in full operation at the company’s Tinaja Hills Proving Ground facility, where 500 kW of solar PV power along with 500 kW of short-term energy storage in the form of batteries and ultra-capacitors were on hand to supplement power that previously had been supplied solely by three C15 410-kW diesel generator sets. The system is expected to reduce fuel consumption by approximately 33 per cent.

Rick Rathe, General Manager, New Ventures told the assembled, “With the declining cost of renewable energy sources and rapid advances in energy storage technology, the time is right to provide an integrated application for remote power.”

In a hybrid microgrid, renewables can account for any percentage of the load depending on conditions. Excess energy produced by renewables is stored for stabilization as well as for use during unfavourable conditions, such as cloudy days and at night. Generator sets supplement the system by powering the microgrid when energy from other sources is absent.

Cat Microgrid applications can come in a variety of combinations:

• thin-film solar modules, which capture more energy, especially in high-temperature, high-humidity, desert, and coastal climates;
• energy storage such as ultra-capacitors, lithium-ion, or rechargeable metal-air storage that provides the most economical and advanced energy storage with controls and monitoring down to the cell level;
• Cat generator sets powered by diesel, heavy fuel oil (HFO), natural gas, biogas, or dual fuel, offering high power density, high-part load efficiencies, and excellent capability to follow loads; and

• the Cat Microgrid Master Controller to monitor and optimize power usage in the microgrid.

Caterpillar has invested in Fluidic Energy for energy storage, signed a strategic alliance with First Solar for an integrated solar PV solution, and made an equity investment in Powerhive, an energy solutions provider for emerging markets.

Steve Niehaus, Caterpillar Vice President with responsibility for the Electric Power Division reinforced the driving motivation for Cat’s interest in pursuing the roll out of the equipment.

“1.2bn people worldwide don’t have electricity – we’re serving a lot of those regions with our core products. They are telling us they need more efficient reliable, and green power. They’re telling us they need to reduce their total owning and operating costs. This why we are in this space for many applications for the military for many years and now we are taking this out to the world.”

The trends the company is seeing, adds Rathe, prompted Cat to look at leveraging the strength of its dealer network to provide global support. He mentions 2008 when Germany was leading the charge in solar, it was $5 per watt for solar panels. In eight years the industry has succeeded in drastically reducing its costs from that level.

“Since we’ve gotten involved with our partners, First Solar, we’ve seen those trends have continued and we continue to see that improvement in prices on the panels and how efficiently you can put them in the ground and integrate those technologies together to really lower the LCOE. That’s why we have accelerated our efforts and moved from telecommunications and military applications to go in to a lot of new markets, going fast and going global.”

“What’s beautiful about it is we can bring our customers better value, bringing them lower costs of energy. By leveraging the best of both we can bring not only below cost of solar PV energy but also firm continuous power – that really is what the microgrid is all about.”

Caterpillar is focusing on remote areas not connected to the grid, but where integration of renewables is an obvious possibility. In essence the generator –panel – storage combination allows sets to be turned on or off depending on amount of solar power available, again impacting on LCOE.

Solar is naturally the lower cost energy in comparison with diesel, which has a knock on positive impact on the company’s customers’ costs.

“We can reduce the amount of fuel consumed anywhere from 8-10 per cent plus depending how much energy storage we integrate into the system.”

“In cases of rapid drop off when a cloud flies over – the energy storage we integrate into our microgrid really helps us to buffer that so instead of trying to turn on a generator set to take up that loss of energy coming from the solar field we are able to use energy storage and that can be a short duration of energy storage, 10 – 15 minutes say, to try keep constant frequency of voltage on the grid for the customer. If we had to do that with just a generator set we are limited in the amount of energy storage you can put in there”

The overriding objective is fuel savings – saving money based on what fuel the customer burns. Using a baseline in terms of what it costs to produce energy and how much fuel burnt through generator sets the company is seeing 2- 5 per cent savings.
Caterpillar hybrid microgrid infographic
Based on 10 MW of multiple generator sets CAT say they can save the customer fuel without any PV by just putting energy storage in virtual spinning reserve.

“We have an energy storage product which allows us to not have as many generator sets running at any given time in case we need the energy storage to pick up the demand. If there is a spike in demand we use virtual spinning reserve instead of having generators.”

Caterpillar identified the leading technologies, in terms of inverters, PV and storage to compile its solution, brought them into the Caterpillar network, branded and integrated them in factory engineering, and developed a scalable plug and play system for dealers.

In addition the company will monitor and support the solution for the next twenty or 30 years, in excess of the life cycle of a modern day solar panel.

Caterpillar are particularly happy to have secured partnership with First Solar, who Steve Niehaus refers to as of ‘the top tier providers in our mind’. Strong financially and a good cultural match, First Solar’s thin film solar panel technology has taken big leaps in efficiency.

“Over the last five years they have invested a tremendous amount of research and development and have continually increased the energy efficiency of their panels. In 2016 they announced 21.2 per cent cell efficiency and 18.3 per cent dual efficiency. We are fortunate to be aligned with them as they are mainly focused on the utility scale. For Caterpillar it’s a great strategic fit – with the best technology in the marketplace and our distribution network to go after the commercial and industrial PV and microgrid spaces.”

Another quality appealed to Caterpillar about the thin film technology First Solar uses. Thin film has an energy capture capability.

In the real world, under standard conditions, their panels get hot but lose less efficiency than a multi-crystalline when it get hot. This is important for Caterpillar as panels don’t degrade to a great extent withstanding higher temperatures, and most of the places Caterpillar operates panels in have those high temperatures.

“As well as the superior temperature co-efficient we get a better spectrum response from the thin film panel. When it’s humid we get more energy out of the panel. We also get better shading response. When a cloud comes over we capture more energy on the spectral range.”

“We can see up to 11 per cent more energy from the thin film panel from all those advantages. That gives us the differentiated product we have in this space.”

Bidirectional converters also allows leveraging of the best energy storage technology whether that is ultra-capacitors, lithium iron or zinc. If a few seconds of energy storage are needed, ultra-capacitors are the way to go (grid stability). If a few hours are required lithium ion products work best.

When four hours or more are needed, time shift energy storage, that’s where zinc products provide the most return on investment for customers.

“We made an investment in Fluidic Energy who have customers at over 600 sites, operating in the jungles of Indonesia over the last five years. They have repeat customers who love the product that’s been in the field, and proven to work in the harshest environments in the world.”

The company can then harness its enduring value proposition – its dealer network. Despite failures in the solar field when it comes to deployment in rural territories there is a trust in the Caterpillar brand that it will have parts available and services support.

Rob Schueffner told Decentralized Energy certain criteria have to come together in order for the hybrid microgrid to make sense. The first thing they look for in an under developed country is a stable government, with a vision, commitment and desire evident across all departments.

“We don’t just want the energy minister who wants electrification, it’s also the minister for health who wants power so as to ensure vaccines are refrigerated, clinics have instruments. It’s the education minister wants power for schools, assisting people who study at night instead of spending money on candles or kerosene –it’s a consensus across government.”

Digging deeper, Schueffner says the technology can replace a cumbersome way of life for many in the world’s margins, where electricity is very much a privilege rather than a right.

“Deforestation is happening but why is it happening? Because people are using wood for cooking and for light, spending lots of time and money getting the charcoal and the kerosene –costing them more than $2 per KWhr equivalent to get light and heat. So we look at what the potential is to bring cost effective electricity there.”

“You can cut costs by 50 per cent and still have a high electricity rate and improve the quality of life for those indigenous groups. You’re talking about a quality of life impact that is so dramatic.”

Referencing the movie Field of Dreams, Schueffner says, “If you build it they will come. We’ve already seen with micro hybrid projects some of our dealers have performed that you may have a location with no people. Once the system is in place, the economy starts around it, with trade, food, health, education – that flame is the start of a society.”

“We’re putting in hybrid systems where people previously knew nothing other than 100 per cent diesel. Now we’re often displacing two thirds of that diesel, but they still have the peace of mind that it’s there.”

Caterpillar has been developing their offering for 7 or 8 years, creating small programmes for telecommunications, getting to know the market and developing intellectual property and patents with some of their operators for key components and pieces that are enablers, systems such as bidirectional inverters, that are differentiated and can be used in other machines.

It all feeds into that drive which has marked Caterpillar out since its inception.

“We want to help those communities into the 21st century. We had provided diesel gensets to jungle and island communities. We continue that where diesel may not be the right product due to access and delivery. It’s a continuation of the legacy of Caterpillar getting power out to help people and a natural continuation where we are now able to do that with renewables.”