Eco-Friendly Cooling Equipment is Coming

Mechanical Cooling Needs to Use Less Energy and Avoid Dangerous Refrigerants

Heat waves are becoming more frequent, more extreme, and more widespread. Air-conditioning (AC) is ubiquitous in the U.S. (90 percent penetration), but not in Europe and many other regions where it is increasingly becoming a necessity. Outside the U.S., less than 25 percent of people in regions that merit AC have it. Consequently, the International Energy Agency expects AC energy consumption to triple worldwide by 2050.

Unfortunately, AC, in its current form, carries significant environmental costs: More demand for cooling leads to more warming of the planet. In addition, the refrigerants used in cooling condensers are 2,000-3,000 times more potent than carbon dioxide as a climate-warming agent when it leaks into the atmosphere.

Gradient Comfort, a San Francisco–based company, is tackling AC’s climate predicament — their mission is to push the industry to zero carbon emissions. Gradient has developed an innovative window cooling and heating unit that is both efficient and eco-friendly. It is a heat pump, a technology gaining in popularity for centralized heating and cooling systems because of energy efficiency, but such equipment tends to be bulky, expensive, and requires professionals to install. Gradient’s technology, however, offers a sleek, affordable, and compact alternative. 

The only Gradient model currently available (it only came on the market this summer) is a window unit. It sells for $2,000 compared to $5,000 or more for comparable units. Their saddle bracket fits on the windowsill of a single- or double-hung window and holds a sleek, attractive fan-coil unit on the inside while the evaporator heat pump is on the outside. Both components fit below the window, so that views are not obstructed. Housed with the fan coil is a quiet fan, eliminating any noise issues. The company is designing other models to fit other styles of windows, e.g., casement units. The unit is planned for do-it-yourself installation in 15 minutes with just a few basic tools. 

Gradient won the Fast Company’s 2022 World-Changing Ideas Award. The cooling component is 30 percent more efficient than traditional window units. When both heating and cooling are combined, the improved efficiency jumps to 75 percent. Another big plus is the refrigerant: Although still a hydrofluorocarbon, the fluid used by Gradient has a quarter the global warming potential of those used by other AC manufactures. They are working to improve their refrigerant even more.

The Gradient device is designed to use only the amount of energy required as it is turned up or down. It is also linked to Wi-Fi in order that it can be self-adjusted when there is heavy demand on the electric grid.

Although Gradient needs more improvements to reach its goal of zero greenhouse-gas emissions, it has taken big first steps in addressing the widespread flaws in existing systems: high cost, cumbersome installations, and unsightliness. These are important directions for widespread adoption of cooling including in less affluent areas of the world.

The Lompoc Strauss Wind Farm

Santa Barbara Is Well on the Way to 100 Percent Renewable Electricity

A small group of us had the privilege of recently touring the Strauss Wind Energy Project in Lompoc while it is under construction. It is the first and only wind project permitted anywhere along the California coast. From the first earlier permitted version of 65 generators, it has been scaled back to 27 machines, yet with the capacity to produce 100 megawatts of electricity.

Reducing the number of turbines has significant environmental and economic benefits. Major advances in “wind” technology during the past 10-15 years have boosted the output possible for a single generator. Each Strauss platform is rated at 3.8 megawatts, the largest land-based turbine available in the U.S. Blades are 227 feet long, the towers 492 feet tall. Scheduled completion date is December this year. Once operational, project will produce the electricity to power 45 thousand houses. For the next 30 years, it will keep six million metric tons of CO2 from entering the atmosphere and warming the planet. This is the equivalent of not driving 16 billion miles. In addition, it will infuse $40 million into Santa Barbara’s tax coffers.

The next wind project along the California coast will likely be offshore, either in the ocean off Morro Bay or off the coast of Humboldt. Both zones have received federal and state approval and are being readied for bulk permitting. The Biden administration recently approved a Massachusetts plan for the nation’s first commercial-scale offshore wind farm. A dozen other East Coast offshore wind projects are now under federal review. Unlike the East Coast, California faces the logistical challenges posed by a deep ocean floor. Evolving technologies, developed mostly in Europe, now make wind generators on floating platforms feasible, as well as even larger ones than land-based units. There is a wind farm with 6-megawatt turbines operating in the North Sea. There is also a 14-megawatt turbine that has been successfully producing for two years in Rotterdam Port.

Santa Barbara has set a goal of 100 percent renewable electricity by 2030. The adoption of community choice energy programs in the Tri-Counties, an initiative advocated and led by the Community Environmental Council, now has 1.4 million households getting at least 50 percent of their electricity from renewables, and many as much as 100 percent. All will be getting to the 100 percent goal by the end of this decade. The Strauss wind farm, when it comes online, will be a big component of local clean energy production.

Wind energy is an ideal complement to solar energy because winds tend to be strongest in the evening and at night. The distributed photovoltaic panels on buildings throughout the County together with the 40-megawatt Cuyama solar farm and the 100-megawatt Strauss wind farm will produce about two-thirds of the electricity Santa Barbara consumes. The county is well on the way to meeting its 2030 goal.

Electric Homes Run Off Sunshine

Harnessing the sun for our electricity, hot water and space heating is practical and cost effective whether remodeling or building from the ground up. After maximizing use of the sun, consider going all electric, since some or all of your electricity can be site-generated. When pursuing this strategy, it is most cost effective to reduce electrical loads (LEDs, Energy Star appliances, etc.), as fewer photovoltaic panels will be needed.

Heat pumps fit nicely into this strategy. They can heat or cool a home, provide domestic hot water, refrigerate your food and even dry your clothes. Heat pumps use electricity to move heat from one place to another instead of generating heat directly. Their high efficiency results from their capacity to transfer more energy (heat) than the energy they require to operate. They are rated by COP (coefficient of performance), the ratio of useful heating or cooling provided compared to the work required. Although they have been around for many years, recent improvements greatly increase their efficiency, achieving COPs in the 2-3 range (compared to 0.8 for efficient gas furnaces or water heaters). Variable-speed motors and scroll compressors in lieu of piston compressors are key recent advances that lower energy consumption, minimize noise and reduce maintenance. Heat pumps work best in moderate climates.

For the non-scientist, heat pumps conjure up notions of alchemy: extracting heat from already cold outside air and transferring it inside to heat the home, or when it’s hot outside, reversing direction to act like an air conditioner, removing heat from the home.

Heat pump appliances such as refrigerators, dryers or water heaters have condensers built in, while space conditioning heat pumps have two main components—an outdoor condenser and an indoor air-handling unit. In recent years, mini-split or ductless units have become popular, because of their small size and zone heating/cooling capabilities. Many models can have as many as four indoor air-handling units connected to one outdoor compressor. Each zone has its own thermostat for optimum control. It is critical that each unit be properly sized for its space to run at maximum efficiency.

Mini-splits are quick and easy to install and offer great design flexibility. They are especially practical for additions and remodels. Ductless systems offer multi-stage filtration that can drastically reduce dust, bacteria, pollen, allergens and other particulates in the air.

Heat pump equipment costs the same or slightly more than comparable natural gas equipment, but if run off sun-generated electricity, the savings add up rapidly. Even if run off utility-generated electricity, the super efficiency, along with the 30 percent federal tax credit, makes it the more economical choice. I am convinced that the all-electric home run off the sun is the future.

Electrify, Electrify, Electrify

Each Time We Replace an Appliance Is an Opportunity to Reduce Warming Emissions 

Until recently, most of us have not had choices about the power we consume: the gas for our cars or the fuel used to produce our electricity. Most supply-side choices are made by giant corporations. Fortunately, the game is shifting, at least in California and a few other states, where community choice energy programs with more clean energy, often 100 percent, are increasingly available. Santa Barbara, City and County, now have community choice programs. This is changing the supply side of the equation.

On the demand side, however, we have always had more influence: We decide what we drive, how we heat our water, what heats our house, what cooks our food, and what dries our laundry. For the past 50 years, the climate focus related to the machines and appliances we routinely buy has been on efficiency — mandated vehicle fuel standards, tighter houses through more rigorous energy codes, and Energy Star appliance performance ratings. Efficiency policies are not going to get us to zero emissions, however, certainly not fast enough to address the urgency of the climate crisis. Electrifying everything can, however, go a long way toward solving the problem — and rapidly. How fast? As fast as appliances need replacing: cars roughly every 10-20 years, home furnaces about every 20 years, and kitchen and laundry appliances every 10-15 years. 

Thankfully, we now have good choices for these replacement purchases, and they are getting better every year. Electric cars currently have good range, are close to cost parity with combustion cars, and save money every mile we drive. Air-source heat pumps for heating, cooling, and hot water now perform four or more times better than traditional appliances. The modern induction cooking experience is better than cooking with gas and is twice as efficient.

Dispersed rooftop solar can be the cheapest energy source, but we make it cost more than it needs to by cumbersome, lengthy permitting and inspection requirements. Whereas the installed cost is around $1 per watt in Australia, it ends up near $3 per watt in the U.S. When the U.S. is fully electrified, 20-30 percent of electricity can be generated locally on rooftops, and the remainder will need to come from wind farms, utility-scale solar farms, geothermal wells, and hydroelectric facilities.

Thinking about addressing climate change can be overwhelming and depressing. Replacing fossil-fuel equipment with electric units will enable us to be and feel part of the solution, without sacrificing the conveniences of modern life. Moreover, the long-term economic benefits are not only in utility bill savings, but in creating jobs. Several studies link 25 million new jobs to mass electrification in the U.S. Many of these will be local.

Once we shift to clean energy, we’ll be able to enjoy all the comforts — warmth, air-conditioning, zippy cars, and hot water — but with lower costs and cleaner air.