QUESTION: My old central air conditioner still works, but I wonder if I should replace it with a super-efficient one. How much can I expect to save on my electric bills? Are the new natural gas cooling units efficient?ANSWER: Your old air conditioner probably has a SEER (efficiency ratio) of about 6 or 7. A new super-efficient electric unit has a SEER of 15. Installing one can cut your cooling costs by more than 50%. New natural gas central air conditioning units have an equivalent SEER as high as 27.New super-efficient electric air conditioning units use two-speed compressors and variable-speed indoor blowers. On the low energy saving speed (runs at high speed only on the hottest days), each cycle run time is longer. Indoor temperature swings between on-off cycles are virtually eliminated.The air gently circulates almost continuously and noise is reduced. With soft start, the initial burst of warm (cold in the winter) air from the ducts is eliminated. This is ideal for allergy sufferers because air cleaners are more effective and humidity levels, mold, mites, etc. are reduced.

The indoor blowers use special electrically commutated motors. These not only provide true variable-speed operation for better comfort, but they use less than half as much electricity as standard blower motors.The most efficient single-speed air conditioning units use scroll compressors. Scroll compressors have fewer moving parts than standard reciprocating piston compressors. window ac unit energy usageWithout pistons and valves, scroll compressors are quieter too.hvac units costsAs scroll compressors wear over years of operation, they seal better and operate smoother than when they were new. using window ac unit with central airTheir basic design is reliable, and they should continue to operate at high efficiency levels for many years.If you have natural gas, there are gas-powered air conditioning units that use a no-compressor absorption process.

These also heat your house in the winter.Another super-efficient gas central air conditioning and heating unit uses a compressor. With an equivalent SEER of 27, it can cut cooling costs by 75%. It looks just like a standard electric central air conditioning unit outdoors and is quieter.A small natural gas-powered engine runs the compressor. Since an engine can run at any speed, its microprocessor continually, fine-tunes the cooling output (17 levels) to the precise cooling needs of your house.In the winter, this year-round gas air conditioning unit heats your house at more than 100% efficiency. It combines the heat pump principal with the excess heat from running the engine. This can cut your heating costs by half too.Write for Update Bulletin No. 528 showing a buyer's guide of super-efficient gas and electric central air-conditioning manufacturers listing efficiency, cooling capacity, compressor type and number of speeds, features and a savings-selector chart. Please send $2 and a business-size self addressed, stamped envelope to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, OH 45244.What Sun Room Design Is Most Efficient?

Q: I am planning the addition of a sun room to my house. I will use it for growing some plants and hope to get some free solar heating in the winter from it. Should I get one with a slanted or vertical front?A: Get one with a vertical or near vertical front. Although the slanted front designs are usually less expensive, they tend to overheat in the summer, even in northern climates.If you plan to use your sun space to help heat your house in the winter, include adequate solar mass. This is often accomplished with a heavy brick or concrete floor. You will also need a fan to move the warm air indoors.Letters and questions to Dulley, a Cincinnati-based engineering consultant, may be sent to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, OH 45244.Gas Heat Pump Air Conditioning System (GHP) GHP function and benefits Yanmar Gas Heat Pump (GHP) air conditioning systems provide high efficiency and cost effective heating and cooling solutions for buildings using gas.

Being mainly powered by gas, these GHP systems can give low running costs, reduced CO2 emissions and eliminate the need for expensive electricity supply upgrades that are often required by electrically powered heat pump systems. They can also reduce seasonal overloading of electricity grids, create new opportunities for gas to be used for cooling and also help to stabilize the demand for gas and electricity over the year. GHP operation and key features GHP systems operate by using energy from gas to power a gas-engine which then drives the heat pump. The heat pump transfers large amounts of heat energy between the building and the outside air; this heat transfer is done between indoor units fitted in the building and an outdoor unit installed outside the building. Heat transfer with the outside air is done using heat exchangers built into the outdoor unit so no other heat source or heat sink construction is required, this with the small footprint and quiet operation of GHP systems means that GHP systems can be installed in a huge variety of locations.

The gas-engine used in Yanmar GHP systems is an example of Yanmar’s own lean-burn gas engine technology which provides a world-class combination of efficiency and reliability. Since engine heat can be reclaimed and used for additional heating GHP systems have particularly high efficiency in heating mode, this also means that these heat pump systems still have high heating output even with low outdoor air temperatures. With a wide range of indoor unit options, these Yanmar GHP air-conditioning systems offer precise control and great flexibility to ensure all year comfort in all kinds of applications. Yanmar GHP systems are ideal for restaurants, shops, showrooms as well as hotels, office buildings, schools, care-centers, sports clubs, factories and a multitude of other applications. Remote Monitoring Service Login Page（GHP/CP） Gas Heat Pump Air Conditioning System (GHP) Inquiries and SupportThe energy startup scene is awash with companies claiming their new widget or software platform will fundamentally change the way we use energy.

Too often, these claims come with a sizable side of hype that clouds serious limitations to real energy savings and market adoption. But every once and a while, a technology comes along that combines the right technology with the right use case to be truly transformative. Florida startup Be Power Tech’s hybrid fuel cell and air conditioner is one of those technologies. The simplest way to describe Be Power Tech’s system is an air conditioner that runs on natural gas and produces some bonus electricity on the side. The fact that the air conditioner runs on natural gas — an energy form that can be easily and cheaply stored — alone makes it innovative. Shifting some cooling power to natural gas would substantially reduce peak summer power demand, and help to reduce the need for costly peaking power plants. But what makes Be Power Tech’s technology truly innovative is not the fact that it produces air conditioning from natural gas, but that it does so by combining two techniques that give it a decisive advantage over conventional air conditioning and energy generation technologies: evaporative cooling and waste heat utilization.

Evaporative Cooling for Low-Power Air Conditioning Conventional air conditioning works by compressing a refrigerant using a high-power motor until it transforms from a gas into a liquid under high pressure. Then, the liquid refrigerant is pumped into a device called an evaporator, which essentially sucks heat out of the building as the refrigerant evaporates from a liquid back into a gas. The electricity consumed by the air conditioner is mostly for the compressor that is used to turn the evaporated refrigerant back into a liquid. The loud buzz you hear from an outdoor air conditioner is the sound of the compressor doing its work. Rather than a conventional compressor-driven air conditioner, Be Power Tech’s system uses an innovative desiccant-enhanced evaporative cooler originally developed at the National Renewable Energy Laboratory (NREL). The company has obtained an exclusive license from NREL for use of the technology. Like a conventional air conditioner, an evaporative cooler absorbs heat from inside a building using evaporation.

Hot, dry air is conditioned by pumping it over a pool of water that slowly evaporates and causes the air to become cooler and more humid as it passes through the system. An evaporative cooler or swamp cooler sucks heat out a stream of hot, dry air by slowly evaporating a pool of water. (Credit: Nevit via Wikimedia Commons) Evaporative cooling is by no means a new technology. You can buy an evaporative cooler (also sometimes called a swamp cooler) for just a few hundred dollars. The problem is that they only work when the outside air is hot and dry. This means they can’t be used in the vast majority of the country, because the air is just too humid in the summertime. To overcome this limitation, Be Power Tech’s cooling system uses a desiccant to suck water out of the air before it is chilled through evaporative cooling. The desiccant is a liquid salt solution that has a high affinity to absorb water from air. With the addition of the desiccant, the technology achieves all of the benefits of an evaporative cooler without the limitations that restrict conventional evaporative coolers to dry regions only.

Be Power Tech's system uses a desiccant-enhanced evaporative cooler to get all of the energy-savings benefits of evaporative cooling without the limitation of not working in humid climates. (Courtesy Be Power Tech) But to work properly, the system needs some way to get water out of the desiccant so that it can be continuously used to extract moisture from incoming humid air. That’s where the system’s on-board fuel cell comes in. A Heat Source That Makes Electricity on the Side To dry out the desiccant after it has absorbed water from the incoming humid air, Be Power Tech’s system uses the waste heat produced by a natural gas fuel cell. The heat evaporates water from the liquid desiccant and dry, “charged” desiccant is stored in a tank until it is needed. A natural gas fuel cell converts natural gas directly into electricity through an electrochemical process that essentially strips electrons from the incoming hydrocarbon gas and turns it into a mixture of water vapor and carbon dioxide.

Any fuel energy that isn’t converted into electrical energy is rejected as heat. A typical natural gas fuel cell converts about half of the incoming fuel’s chemical energy into electricity and half into heat, and operates at about 600 degrees Celsius. Normally, natural gas fuel cells like Bloom Energy’s “energy server” operate to produce electricity for sensitive loads like this eBay data center and reject produced heat to the environment as a waste product. Be Power Tech’s system works the other way around by using the fuel cell as a source of heat to dry out the desiccant used in the air conditioning side of the system. The electricity produced by the fuel cell is then fed to the building where it can be used for lighting, computers, and all sorts of other commercial loads. The advantage of operating in this way is that nearly all of the chemical energy contained in the natural gas fuel can be used for something useful — resulting in less energy consumption overall.

According to Be Power Tech, their system uses over 80 percent of the chemical energy in the input natural gas to either make electricity or provide air conditioning. Everyone Wants a Better Air Conditioner Be Power Tech’s system might sound complicated, but in essence it is a drop-in replacement for a conventional rooftop commercial air conditioner that runs on natural gas and uses a lot less energy to produce the same amount of cooling. This means that building owners could see a huge reduction in energy costs from installing the system, especially with today’s low natural gas prices. To bring its technology to market, Be Power Tech is conducting tests of the system under various atmospheric conditions and use cases in partnership with Oak Ridge National Laboratory. The company expects to begin field trials of the system next year. If they can prove the system’s benefits under real-world operating conditions and communicate its value proposition to commercial customers, I expect they will see rapid adoption of the technology.