Category Archives: Sustainable Solar Air Conditioning

hybrid solar, 100% direct current, battery friendly air conditioning


Solar systems have been installed at an amazing rate in California over the last 10-years. Something incredible happened in 2007 that exploded the solar industry called the FITC or federal investment tax credit or ITC for short. This long term federal commitment to a simple, no limit 30% rebate on the installed cost of a residential or commercial PV system caught the imagination of some of the most talented business minds in America. The ITC encouraged the finance industry to plan long term and develop products that allowed businesses and consumers to buy in knowing it made good financial sense to do so. This marshalling of minds and resources combined to take solar capacity in California from about 500 megawatts in 2007 to over 20,000 megawatts today according to the California Public Utility Commission. That’s the difference between the sun powering 125,000 homes in 2007 and solar systems powering over five million homes today. This does not include the additional energy contributions of hydro electric, wind turbines, solar thermal hot water systems and a variety of other renewable energy production methods. It’s estimated that another 15,000 megawatts of solar capacity will be added in California through 2021 and by legislation at least 1,300 megawatts of battery storage capacity is to be achieved by 2021 as well. According to HIS Markit, the current federal ITC law allows a 30% rate for projects started through 2019. In 2020 the ITC rate will be 26% and in 2021 the rate will be 22%. If no ITC program extensions are adopted or a new ITC program is not signed into law the incentives will end in 2021 for households and in 2024 for commercial, (commercial projects must begin in 2021). For now though, the federal ITC combined with the California SGIP incentive for battery storage that’s in effect through 2020 will keep demand for new installs high while encouraging system owners to upgrade and enhance their existing systems.

Within these massive former and future install numbers lies the inevitable maintenance requirements that will begin to appear as installed solar systems, (especially roof mounted PV and thermal systems) age. Roof and system leaks, solar panel, panel wiring and inverter failures, shade creep, battery and monitoring equipment failures, human/nature caused obstruction and destruction and an assortment of other issues will become as common as all of the previous installations were.  As these maintenance issues multiply, solar system owners will need to be able to call on ethical companies that can accurately identify problems, repair and upgrade and then professionally apply any applicable warranties and incentives. A solar service company, (SCC) must have a skill set that goes well beyond your typical solar install company to accomplish this.


Some of the most important aspects of a SSC is to be licensed and familiar with all applicable local planning and state codes, the vast array of solar products that have been and are being installed in their market and the ability to professionally administrate each job to a successful conclusion.  Additionally, an SSC must have a deep knowledge of the types of roofing structures and roofing materials available in its markets and of the utility grid connected electrical system and codes that support these markets. If the company is serving solar thermal systems, the same criteria would apply to the various aspects of the solar thermal system’s plumbing and its interface with the building plumbing and applicable codes. With these areas of expertise covered by the SCC, it’s possible to field a staff that can perform site surveys to identify and diagnose problems and or potential upgrades, generate an accurate quote and complete the repair and or upgrade to the owner’s satisfaction. The SCC may be independent, part of an existing solar system installation company or a division of a roofing or energy efficiency company. Regardless of the company’s structure, they all should be a licensed contractor in good standing and able to professionally respond, diagnose, quote, repair and apply any applicable warranties and incentives to all serviced systems.


In addition to repairs there will be a large demand for solar PV system upgrades, expansions and enhancements. According to NREL, solar panel efficiency has increased from 17.8% in 2012 to 22.8% in 2015 and to 29.8% in 2016 while solar panel costs have dropped over 50%. At this rate, tens of thousands of solar PV system owners will want to switch out their older panels with ones that are cheaper and two to three times more efficient. In most of these cases the old inverter and monitoring system will also need to be replaced and a battery charging and storage system may be added. This efficiency upgrade will naturally add more solar capacity, (more watts) to a system and will be an option many owners that add batteries will want to take advantage of. A study from the University of Texas at Austin found that battery storage in a home solar system increases annual power demand by up to 14%. Throw in a new electric car and the natural inclination to use more power when a PV system is present and the added annual household power requirement could easily top 20%.

Companies that successfully offer system repair and upgrade services will be the best positioned to take advantage of the tidal wave of service and repair demand that will hit over the next few years. These same companies will also thrive as solar system owners discover how profitable it is to upgrade and enhance their systems.

Metal Roof Mount Solar PV System in SOCAL


Since it just became hot in Southern California and in about a month you’ll open your power bill to rediscover the financial outrage that faded last Fall, you may want to implement some of these easy and cheap energy saving tips. With electricity rates changing, energy prices going up and the heat sticking around longer you’ll have more to spend on funner things.

First, evaluate your current SCE rate and determine if going to TOU early will save money based on use history. This alone could save you up to $500 this year*.

Second, if you have not switched your high use lighting to LED now is the time. Removing old bulbs inside and out can save up to 90% and significantly reduce your heat gain inside.

Third, spray clean your outside compressor/condenser; this can add 5% efficiency to your AC operation. Replacing the inside AC air filter and setting your thermostat a degree or two warmer or replacing it with a programmable t-stat could save up to an additional 10% on AC operation.

Fourth, make sure your doors and windows close snugly and if they are not, replace the weather stripping and caulk around any “leaky” areas. This can squeeze another 5% savings from the AC operation. Shading sunny side windows and doors outside will help as well.

Fifth, check your HVAC ducting for leaks, add an attic fan and add some insulation in the attic. Ducting leak repair and additional Insulation benefits year round and an attic fan can keep your ceiling inside 15-20 degrees cooler. This can add up to 20% in additional AC operation savings.

A portable AC unit in a main living or bedroom to augment, your central unit, ( ) can also work well when you combine it with a programmable thermostat.

Thinking about a grid-tied rooftop solar PV system? Hardware prices have gone down but regulatory and interconnection costs have risen so do your homework. Sometime identifying an area of power consumption and minimizing that, (a variable speed pool pump or a soft start AC unit) may be your best path. See the incentives at the link below.

Solar Credits & Rebates:

*SCE New Time of Use Rates:

If most of your electrical use is 2pm to 8pm and total monthly use is over 700kWh, the TOU kWh rate for that time can be $0.32, $0.33 or $0.44/kWh in addition to the delivery & generation charges, taxes and other fees.

So pick something, anything and save money.

Have a great Summer!


In the world of air conditioning, air cooled chillers have always been more efficient than conventional refrigerant based air conditioners, up to 300% more efficient in some cases. The problem was that these chillers are usually over 10-Tons in size and most home/office air conditioners specified or installed are refrigerant based systems and less than 10-Tons. So 95% of the time designers and builders use ducted 3-Ton and 5-Ton, refrigerant based air conditioning or heat pump systems in new construction, small commercial and replacement projects. In addition, no thought was expended on how a climate control system could add to hot water production and take advantage of solar thermal and or electric systems designed into or existing at an increasing number of new and retrofit projects.
Chiltrix has thought about these opportunities and recently updated its CX34, 2-Ton mini-chiller heat pump listing on the California Energy Commission web site to incorporate the CX34’s world record setting efficiency data recently certified by AHRI.
As a high quality chiller with a 20-year service life, multiple air handler capability, scalable from 24,000 to 72,000 BTUs of air conditioning, ductless split with variable speed motors; the CX34 checks all the boxes when it comes to being ultra-efficient and dependable. It leaves other comparable units 37% to 150% behind in ILPV EER efficiency and up to 300% more efficient under NLPV conditions. Both ILPV and NLPV are specified in the AHRI’s, (Air Conditioning Heating Refrigeration Institute’s) 550/590 industry Standard. ILPV is what SEER is to standard air conditioners, the NLPV rating is used for the CX34 when its humidity control option is in use and loop water temperatures fluctuate out of the ILPV standards to maintain a desired indoor humidity level.
The patent-pending Chiltrix offers a DHC humidity control option which is unique to the CX34 and allows users to set specific inside humidity levels higher for a healthier inside environment while saving even more energy during its operation. Other systems cannot provide this important aspect of total indoor climate control.
To put the efficiency of the CX34 in perspective, let’s look at a new 100 home project in southern California, (at least 20-miles from the beach) with an average of 1200 square feet of living space per home and the CX34 is used for primary hot water, heating and cooling. The residents of this project would have a combined average of an additional $90,000.00 per year of disposable income that would eventually make its way into the local economy or the homeowner’s education/retirement accounts. Either way, the effect is a healthier more prosperous community.
So let’s review:
• The CX34 heat pump has a certified IPLV COP efficiency of 6.75 and an EER of 23.02 using chiller ILPV efficiency rating guidelines from AHRI and a COP of 9 and an EER of 30.72 using the NLPV, (controlling inside humidity levels) rating guidelines. The ILPV efficiency rating is a world efficiency record!

• The whisper quiet, air cooled CX34 chiller is quality manufactured with the best parts from around the world to achieve a 20-year service life, uses insulated PEX water lines to support up to eight ductless inside air handlers per 2-Ton outdoor condensing unit and is scalable to 6-Tons of air conditioning and 9-Tons of heat. The CX34 is an air cooled, sealed and maintenance free chiller heating and cooling system.

• The variable speed motors in the CX34 allow it to have an operating range of 25% to 100% of its rated capacity giving the user the option of only cooling/heating inside areas where people actually are present. If only one ½-Ton air handler is active then just a fraction of power is used by the CX34.

In addition to the CX34’s attributes above; it is solar ready. With a variable speed 208/240 single phase soft start of 2 amps, the CX34 makes it easy on inverters and battery banks and practical to integrate into solar PV systems. It can also connect directly with solar water heating systems for heating purposes and be an ultra-efficient primary source for hot water thus saving the user even more on related energy costs.
Finally the CX34 is priced about the same or less as quality conventional new or replacement HVAC hardware. If ducting or ducting replacement/repair is factored in the CX34 is often the less expensive option. Builders and contractors can also save on new construction and replacement projects by using in-house install personnel since there is no requirement for a specialty license to install the CX34.
New zero energy and Title 24 compliant home buyers, commercial tenants and system replacement customers benefit greatly from reduced AC operation noise levels, a more comfortable and healthier interior environment, contributing to local carbon reduction strategies and saving up to 50% on climate control and water heating related energy costs as a result of the CX34 being the primary hot water, heating and air conditioning system for their home or office.
Yes, the people at Chiltrix thought of that.
Go to: for pricing and technical documents or call; 909.223.7357 at D48 Energy Management to discuss your specific application.


Portable air conditioner capacity & efficiency – The big lie

Today portable air conditioners fly under the federal and state efficiency regulatory radar. Efficiency rating for portables is not required to be third party lab tested and the consumer is at the mercy of the honesty of the manufacturer. Even if the manufacturer is honest with its efficiency results, it’s what they don’t tell you that makes for a difficult buying decision*. By 2019 portables should have federal efficiency standard minimums that incorporate a standard set of testing parameters which will help with eliminating from the market some of the worst performers and a general improvement in customer satisfaction and trust. Until then it’s; buyer beware. There are key quality elements that a consumer in the market for a portable air conditioner can look for.

Portable air conditioners are not like window air conditioners and do not affix to a single window, most are freestanding units that may be moved, (the majority of portables are usually ½ to 1 Ton or 6000 to 12000 BTU and are mounted on rollers or wheels) from room to room and use a single duct tube to exhaust warm air to the outside through the tube and window adaptor sealing plate assembly. These single tube portables typically provide no more than 40% to 60% of their rated capacity in real operating conditions because in the process of removing heat from the inside they draw in hot, humid outside air. The reason for this is that single tube portables use cool dry inside air to send the room heat outdoors causing negative pressure inside the space being cooled and a negative feedback heat loop. This negative pressure caused by a single hose, (imagine water leaking into a submarine) causes hot air and humidity from the outside to be sucked back into the room through the windows, doors, electrical outlets and ceiling. At the same time, they use 100% of their rated power more often and for longer run times than they should by continually trying to remove the heat generated from bodies, cooking, electronics, the dog and cool the accelerated introduction of hot humid air caused by single hose negative room pressure. That means both capacity and efficiency are substantially less than stated by the manufacturer, (manufacturers of single tube portables do not account for negative pressure) which leads to undersized and poorly performing portables, higher than expected electric costs and downright angry, hot customers.

The few portable air conditioners available today that use dual hose technology deliver close to or above their maximum BTU rating promised. Dual hose portables bring in air from the outside through one tube to blow over and cool the compressor and then back to the outside in another tube, (both are connected side by side to a similar window adapter sealing plate) to the outside creating a balanced pressure environment inside the room. This dual hose solution allows the portable to easily remove the heat being generated inside the room while running the compressor much less and keeping operation costs within expectations. A portable that runs its compressor less will last longer, save on power costs and make a happy customer.

Most portable air conditioners use low efficiency “dumb” compressors that are noisy and are constantly turning on and off rather than quiet, high efficiency DC-Inverter variable speed compressors. For the above reasons, portable air conditioners using dumb compressors, (95% of portables made today) generally have and deserve a poor reputation for capacity and efficiency. A portable with a DC Inverter compressor is three times as quiet as portables with dumb compressors and can save 30-40% in electrical consumption. One or two manufactures produce a whisper quiet, dual hose, DC Inverter portable air conditioner today that can save 50-75% in electrical consumption.  It costs more to build an ultra high efficiency, variable speed compressor, dual hose portable air conditioner, but some manufacturers believe that smart customers will pay more provided they can quickly and repeatedly recover the price difference through longer product life, quieter operation and lower electricity costs. These more expensive portables are even built to allow the user to never have to empty a condensate tank making these portables virtually maintenance free, (except for cleaning the air filter).

*But what about portable air conditioner capacity and efficiency ratings? Why the big lie?

It’s not exactly a lie, just an omission, but the result is very misleading. It happens because there is no official US government required test protocol for portable air conditioners. This loophole allows portable AC manufacturers to use generic testing and rating protocols not designed for portable air conditioners. Standards are in the process of development at the US Department of Energy. The test protocols currently used in the portable AC industry for single tube portable AC units are only accurate if conditioned indoor air temperature and outdoor air temperature are the same, (which is not usually the case) on a day when you are using air conditioning. As explained in this document from the US Department of Energy, portable air conditioners are self rated by their manufacturers based solely on the amount of cooling performed between the supply and return on the room-side which ignores crucial outdoor temperature data. According to the Department of Energy, all single tube portable AC units are dramatically over-rated and have much lower net capacity than claimed. All manufacturers know their capacity ratings are overstated, but somewhat understandably, no manufacturer is willing to switch to a rating system that provides lower performance ratings until all other manufacturers are required to do so. The DOE is currently considering new policy that may eventually change the way portable air conditioner units are rated.

Most dual hose, DC Inverter portable air conditioners are tested and rated per proper AHRI 220/240 using both indoor and outdoor temperature test conditions. They are proven to deliver 100% of its1BTU rating. And because of its DC Inverter compressor, it can operate at hundreds of different power settings to match its capacity to current conditions and conserve power at times when full capacity is not needed. Variable capacity DC Inverter systems are known to consume 30-40% less power than fixed speed systems. Dual hose systems provide up to 65% more cooling capacity per watt consumed. Only a variable capacity DC Inverter compressor combined with a dual hose design produces the world’s most efficient portable air conditioner. On average, these portables provide the same cooling for over half of the power consumption, or twice the cooling for the same power when compared to any other portable air conditioner.

A new breed of portable air conditioners

So although there are several years remaining until portable air conditioners are all third party lab tested and rated on the same standards, several portable manufacturers are leading the way by incorporating the best technology now and self testing to standards that may be adapted by the entire industry. There is a new breed of efficient, quiet and trouble free portable air conditioners coming on line and available in the market today and the consumer just needs to look for them.

DIY: Little or No Power Air Conditioning Systems

Imagine one day, in the not so distant future, going to your local home improvement store and buying an economical air conditioning system that easily DIY installs at your home or office and uses little or no power from your local utility.

Climate control of homes and offices, (less than 10-Tons) is the largest single consumer of power today and is growing at a blistering pace around the world. If global trends continue, there will be plenty of inefficient, cheap air conditioners and not enough fossil fuels to keep them running. Fortunately, several sustainable ways of powering climate control equipment have emerged that will alter this dynamic making climate control available to all while easing stress on our utility grids, budgets and climate.

Using the sun and wind for air conditioning is nothing new; wind, solar and geothermal have all worked well in the past. They continue to be utilized today along with new forms of sustainable ground source, absorption chiller, ultra high efficiency heat pump chillers and solar assisted compressor technologies.

There have been substantial cost reductions and hardware improvements in all facets of renewable energy systems, (solar panels, evacuated tubes, wind turbines and batteries) making it feasible to link them with modified mechanical air conditioning technology. When renewables can efficiently supply power to mechanical climate control systems, direct, or through stored energy, the equipment’s capability is fully optimized during the time of day when it’s needed the most.

The oldest and most popular strategy for sustainable climate control is absorption chiller technology. Primarily used in larger applications, (10+ Tons) it is estimated to constitute over 40% of global capacity. With recent advancements in small solar absorption chiller technology, (10-Tons and less) combined with lower costs for evacuated tubes, there’s great potential in the residential and commercial climate control space moving forward. It’s estimated that solar evaporative coolers and small absorption chillers are viable in over 30% of new and replacement, small climate control installs with power savings of over 80%,

New breeds of high tech air conditioning now available are the direct current and AC/DC hybrid ductless split systems or “splits”. These high quality, simple to install splits most common in the 1-Ton capacity, evolved from traditional splits and are extremely efficient with common power savings of up to 85%. Equipped with high efficiency variable speed DC compressors and fans, automated logic controls and using environment friendly 410A refrigerant, they’re adaptable to almost any climate, mission or structure.

Direct current splits are available in 1-Ton, (12,000 BTU) capacity and requires a robust battery bank/charging system sized to the specific needs of the user. The longer the split is required to run, the higher the system cost. Off-grid and grid failure applications requiring quiet operation are best suited for this split with no grid or generator power connection necessary.

Hybrid splits are available in 1-Ton, (12,000 BTU) capacity, Its advantage lies in the way DC solar power directly supplements most of the system’s power needs during the highest demand part of the day and automatically uses grid AC power to make up the difference. No battery bank or power charging system is necessary which cuts installed costs up to 2/3 over the off-grid split. They are best utilized in stable, grid-tied and generated power situations for primary and augmented cooling and heating where power costs continue rising.

The latest addition to the sustainable climate control mix is the ultra high efficiency heat pump chiller. Debuting in 2015, the cooling and heating system takes 240vac, 50/60 hertz power and uses a two or three ton variable speed, direct current compressor to cool or heat water that is then pumped to multiple, (up to seven) remote controlled, programmable air handlers that are equipped with direct current variable speed motors. This estimated 30-SEER system works where the demand is needed, (living areas during the day and bedrooms at night) to replace up to a six-ton system, (72,000 BTU). When deployed to cool and dehumidify electronic rooms in climates that experience Fahrenheit temperatures in the 30’s, the heat pump chiller can operate in excess of 60-SEER, when a simple option is added. These systems are easily scalable up to 30-Tons, are solar ready, (as little as three amp draw at start, directly integrates with solar water heating systems) and are perfect for server room cooling and dehumidification.

These newer breed of sustainable air conditioning systems are a small percent of the current market although some manufacturers are spending serious dollars promoting this space, which affirms the shift. The accelerating market acceptance combined with rapid technical advances, falling hardware costs and a consistent increase in power costs have created the perfect storm making sustainable air conditioning the system of choice now and more so in the future.