FROM ENERGY CONSUMPTION TO EFFICIENCY: AIR CONDITIONING UNDER THE SPOTLIGHT

ENERGY AND ENVIRONMENT

MEXICO CITY: Air conditioning accounts for an increasing portion of electricity consumption in many parts of the world, and Mexico is no exception. While there are a number of energy saving measures, the challenge is to overcome its cost.

FILTER PRODUCTION: Air conditioning accounts for an increasing share of electricity consumption in Mexico, especially in large cities with increasing heat and urbanization. Efficiency measures such as filter replacement, upgrading to inverter systems and maintenance can help reduce energy consumption, but these measures often have high costs that make them unaffordable for many. Air Care Mexico

Tone Aguilar

Published 22.11.2024 - 01:26

“The most important thing we can do to save energy consumed by an air conditioner is good maintenance,” says Fernando de Jesus Bonilla Gonzalez, director of the Mexican company Ingeniería para Ambientes Limpios, Inpal. The company, based in Mexico City, is characterized by adapting air conditioners to the needs of different actors and works to make the equipment as energy efficient and environmentally friendly as possible.

– However, the problem in Mexico is that many people see maintenance as an expense, and when times are hard, this is the first thing to be cut, continues Bonilla González.

DIFFERENT REFRIGERANTS ON THE MARKET

He goes on to say that there are many old air conditioners in Mexico.

MAINTENANCE: Maintenance of air conditioning systems is an important part of Inpal's work and essential to ensure that the systems operate optimally and use as little electricity as possible.

– A few years ago the most common refrigerant gas was R-22, and although it was decided that we should no longer use it because of the consequences for the environment, there are still some old plants that use this gas, says Bonilla Gonzalez.

– Because refrigerant gases work at different pressures, we cannot simply replace R-22 with another gas that is more energy efficient and better for the environment because it may contribute to system failures.

Fernando de Jesús Bonilla González is the founder of the Mexican company Ingeniería para Ambientes Limpios, INPAL in Mexico City.

The most widely used refrigerant in Mexico today is R-410A.

– R-32 is also starting to become more popular, precisely because it is more energy efficient, the Inpal manager points out.

– But, as I was saying, changing the coolant is not a simple thing to do because it involves changing everything, and it may also mean that the ventilation ducts have to be replaced.

Among the improvements and upgrades it makes to any system that is not performing optimally in terms of energy usage is replacing fans or fan motors with ones that are more efficient.

INPAL designs and customizes air conditioning systems according to customer needs. Here they are in the process of installing an Air Treatment Unit for the Petrochemical industry.

– The principle to save energy is to have motors specifically adapted to the fans and the need for air to pass through the air conditioning system, he emphasizes and adds:

– We also have to make sure that there is no dust in the coil and that the filters are not dirty, because then the fans have to work harder and use more energy to make the air pass through.

PRESSURE DROP AND FILTER REPLACEMENT.

The frequency with which filters are changed varies greatly.

Marisa de Segovia, general manager of Air Care Mexico, a manufacturer of filters for air conditioners, notes that both the quality of the filters as the conditions in which the air conditioner is a lot to do in the duration of a filter.

– The pressure drop between the air entering and leaving the filters must be measured to determine when it is time to change the filter, he explains.

– Some filters need to be replaced every three to five months, while other filters need to be replaced once a year.

He further explains that they use the standards of ASHRAE, the American Society of Heating, Refrigerating and Air-Conditioning Engineers, and that they import much of the filter materials.

Marisa de Segovia is the founder and CEO of Air Care Mexico, a company that manufactures filters for air conditioners.

– All the filters we manufacture are additionally certified by laboratories in the U.S. to ensure quality, which in turn helps to save energy, he says, adding:

– We also clean ventilation ducts, and here we use a push-pull system where we create a vacuum inside the pipes where the dust is lifted and then sucked out.

De Segovia stresses the importance of keeping air conditioners free of dust.

– For example, if there is dust in the coil, it will affect the heat exchange and the system will use more energy," he says.

IT'S EASIER TO RUN IF YOU WALK FIRST.

Bonilla González, on the other hand, says that they have had good experiences with electrostatic filters.

– These attract dust electrically and have a larger opening, which means less energy is needed to move air through the system, he explains, adding:

– This type of filter is efficient, does not clog easily, saves energy and lasts longer.

Ventilation duct maintenance is also an important part of Inpal's work to help ensure that air conditioning systems operate optimally.

On the other hand, he stresses how important it is to monitor air conditioners to have an indicator of the pressure difference in the filters, whether the motors and fans are working properly, etc., in order to minimize electricity consumption.

“This monitoring is usually part of a central operating system,” he explains.

– In Mexico in many cases it is done manually, but what we usually do when we upgrade an installation is to acquire frequency converters so that the motors work exactly as needed to pass the required air.

The same applies to the use of an Inverter system, which ensures that the compressor of air conditioners run smoothly.

“These are starting to become more popular in Mexico and save energy by avoiding sudden starts of the compressor,” Bonilla Gonzalez continues, noting:

– It's easier to run if you walk first.

WORK TOGETHER

Among those working on optimizing and reducing the energy consumption of air conditioning systems in Norway is Andre Løvlund. He is leader of the operational team of Entro.

– The first thing we have to do is map; We simply find out what technical equipment is in the building, how much energy the building uses and how much of that energy goes to technical equipment such as ventilation, cooling and heating, he says, adding:

– Before starting the measures, we walk through the building and see if it is possible to reduce the energy consumption as stated.

Løvlund adds that there are quite a few buildings in Norway that have central operations management systems, SD systems.

“Having an SD facility where all the technical installations are integrated is a great advantage, as you get an overview in one place,” he continues.

In energy terms, he points out that there is usually much to be gained by adjusting the joint operation of a building's various systems.

– For example, if you're working with cooling, you can set the set points without thinking about how it affects heating or ventilation, but all the systems in the building are interconnected, he emphasizes.

– So, what you do with ventilation affects heating and cooling, what you do with heating affects cooling and ventilation, and so on.

Although the different parameters set for cooling and heating are different, Løvlund points out that the principles are the same.

– And if the parameters are set incorrectly, it is possible that over time they will become increasingly incorrect and then start to cool down as well as heat up. It is not uncommon for this to happen, he says.

CONTINUOUS WORK

In general, Løvlund says that most buildings in Norway are built incorrectly.

– Of course, there are many good operations managers who can do this, but in a hectic day-to-day life where many buildings are often operated, there is a time constraint that sometimes means they take quick fixes to solve challenges at the time, and fix the heating system, for example, without giving much thought to cooling and vice versa, he says. -Which is a shame in energy terms.

“Optimizing operations is not something you do in a couple of days,” says Entro's Andre Løvlund.

He stresses that the amount of energy that can be saved by implementing optimization measures in a building varies greatly.

– There are buildings that are very well managed and where there is little to save, while other times we can save 10 to 20 percent, and I have known buildings that have reduced energy consumption by as much as 50 percent, he says, adding:

– Operational optimization is not something that is done in a couple of days. There are many control parameters to be tested and, in Norway, the seasons must also be taken into account.

Therefore, they spend about a year optimizing air conditioning systems, occasionally making changes in relation to weather, seasons and the like.

– What we do when we have worked with a building for a long time and have figured out how this building should be to have the best possible indoor climate and use as little energy as possible, is to create operating instructions for the company that operates the building where we tell them, for example, that in March and December they should make specific changes and the like, he says and stresses:

– Optimization is an ongoing process in which the opportunity cannot be missed once it is completed. Rather, it needs to be repaired and maintained, and it is very important that the technical operator is trained on what is and is not a good idea.

INCREASED USE OF AIR CONDITIONING

In Norway, more energy is used for heating than for cooling.

– But there is excessive use of refrigeration, warns Løvlund.

In Mexico and Latin America, cooling is naturally the largest contributor to energy consumption.

“Air conditioning represents up to 60 percent of electricity consumption in a Mexican building,” says Eleazar Rivera Mata.

He is a former leader of ASHRAE Mexico and currently works as a project manager at the Renewable Energy Agency of Nuevo Leon, in the north of the country.

Eleazar Rivera Mata is the former director of ASHRAE Mexico and is currently working to expand the use of renewable energy.

Although the difference between the seasons is not as great as in Norway, it reports an increase in energy consumption in the warmer months of 30 percent.

– This is mainly due to the increased use of air conditioning, he clarifies and adds:

– Furthermore, in Mexico and Latin America in general, there is a growing concentration of people in cities. Globally, it is estimated that 68 percent of the world's population will live in cities by 2050, but by 2030, 86 percent of the Latin American population will be living in cities.

Something that, he points out, will lead to an even greater need for ventilation and cooling of buildings.

– That is why it is important, and will be even more important in the coming years, for air conditioners to be efficient and consume as little energy as possible, he says.

– At the same time, we must strive to make maximum use of renewable resources to cover the energy needs generated by air conditioners, and here solar energy is an excellent alternative. And in Mexico we have the advantage that the time of day when the need for cooling is greatest is also the time when the opportunities for solar energy production are greatest.

SOLAR ENERGY

One of the players specializing in solar cells and air conditioning in Mexico is the company Igloo, based in Cancun.

“There are air conditioners that come with their own solar panels,” says Igloo CEO Elias Herrera.

– But they are not widely used and I don't recommend them either because they have a limit to the amount of energy they can store. The batteries needed to have a stable power supply also need to be replaced every two years, and the systems are not efficient.

Igloo has therefore focused on designing and installing solar panels adapted to its customers' air conditioning systems.

IGLÚ: Solar panels are becoming an alternative that more and more people are using in Mexico to cover the energy consumption of air conditioners. Shown here is one of the solar panels that Igloo has installed in Cancun.

– We analyzed the energy needs of the air conditioners and installed solar panels that will initially cover that, continues Herrera.

– The electricity they produce is immediately used by the air-conditioning units. If the solar cells produce more energy than necessary, it is fed into the national power grid to which they are connected. And if one day there is less sunshine and the solar energy production is not sufficient, it is supplemented by the regular power grid.

Herrera says that about one-third of customers choose to install solar panels along with air conditioning.

– And this ratio is steadily increasing, because while electricity costs for air conditioning are rising year after year, the cost of installing solar cells has decreased, he says.

– Today it costs about a dollar per watt installed, whereas 7 or 8 years ago it cost twice as much.

He is therefore in favor of the use of solar panels in combination with air conditioning and is optimistic about developments in this area in the coming years.