In an environment like the Caribbean – where it’s hot and humid year-round, critical facilities can’t do without air conditioning, and electricity can be unreliable even without disastrous hurricanes – optimizing building cooling systems is more than a major money-saver. It’s essential to an island’s economic and climate resilience.
Caribbean islands face intersecting challenges that amp up the benefits of more efficient energy usage. The constant need for cooling stresses electrical grids that, on some islands, are hanging on by a thread. Most islands import petroleum fuels to generate power, and that doesn’t come cheap – commercial users in Puerto Rico pay more than twice the US average for electricity. Yet those rates are not enough to fund the fleet of plants necessary to support the grid. That means peak usage creates grid instability, which leads to brownouts (periods in which electricity flows at a low voltage that can blow out motors). To compensate for this instability, round-the-clock, temperature-sensitive facilities, such as manufacturing plants, hospitals, and hotels, have to install on-site backup power, typically diesel generation – not the cleanest source.
But those big energy users can play a meaningful role in stabilizing the grid. Serious energy efficiency efforts—beyond the low-hanging fruit – serve not only the bottom lines of businesses, but whole islands as well. Any reduction in peak usage contributes to keeping the lights on everywhere. And the benefits are substantial: among the hundreds of optimization projects we’ve completed around the world, we’ve seen the largest savings at Caribbean sites, particularly in Puerto Rico.
Overcoming Challenges Is Worth the Effort
The financial return on optimizing Caribbean facilities is clear: in this part of the world even a 10% reduction in energy usage produces a major payoff. Energy efficiency – often called the most underused resource – is a true opportunity here, and HVAC systems are the biggest target.
Environmental factors up the challenge level when optimizing systems in Caribbean facilities, but the results are well worth the effort. An optimization of a major global pharma manufacturer we worked with in Puerto Rico illustrates both what’s involved and why taking the time to get it right is so worthwhile.
The facility handles expensive drug products with critical temperature and humidity ceilings, and the optimization encompassed three chiller plants, two involving a major renovation and the third needing minor renovation before optimization. So it was a big project, but the greatest source of complexity was the weather: a beach vacationer’s dream is a chiller plant retrofit nightmare.
Downtime of more than several minutes would have incurred significant costs, and there was no time of day or year when the cooling need and the load were less, so temporary shutdown was not an option. That meant the facility had to figure out how to replace pipes while water continued to flow through them. The answer, in short: the facility connected rental chillers to the system for redundancy, and used hydraulic line stops, typically employed in oil drilling.
The constant heat and humidity also take a toll on mechanical equipment. Operating hours in most geographies allow chillers and pumps to relax and dry out; the lack of downtime here had a stronger effect than anticipated. That factor, combined with the unreliable power supply and the need for a fail-safe system, meant designing a plant with two backups throughout the system. In most cases, we would specify N (the equipment needed on the hottest day) plus one; we learned that the Caribbean environment requires N + 2, because at any given time one piece of equipment could fail while you’re working on another.
Once the redesigned, amply backstopped system was set up, though, the optimization solution produced similarly outsized results. The savings at this facility are the highest in the operating enterprise’s global portfolio of optimized sites. Across all plants, the average efficiency rating improved by 32.7%, resulting in cost savings of more than $2 million in the last year as well as savings of 9.8 million kWh and nearly 8 million pounds of CO2.
Post-project support is crucial to maintaining these results over time. Measurement and verification is always an important element in optimization success, and it’s absolutely essential in hot, humid environments. Without ongoing monitoring and diagnostics, the weather will quickly push a plant back to inefficient operation. With them, the plant will keep delivering energy and cost savings well into the future.
The Payoff
The payoff is more than just a reduction in a large corporation’s ongoing operating expenses (though they certainly appreciate that). Significant savings come from using significantly less power, which means a more stable grid that can reliably serve all customers – including those without the resources to install their own backup power.
Reduced baseload needs also create room to shift from the old power plants to more renewable power generation. There’s justified excitement about the potential for a renewable energy boom in the Caribbean, but it probably won’t happen as quickly as everyone would like. Green energy systems are also vulnerable to extreme weather, and the politics and planning challenges will at least rival those on the US mainland. That leaves energy efficiency – especially by the heaviest power consumers – as the most immediate solution to the Caribbean’s energy challenges.
It’s not always a simple solution, but optimizing Caribbean energy use has both short-term and long-term benefits for businesses and communities: it makes the most of a problematic resource, and it frees utilities to shift some resources toward building microgrids and renewable distributed generation that will shore up long-term resilience.
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