Cooling alternatives for a warming world

Cooling is no longer a luxury but a necessity for health, productivity and survival in a warming world. However, traditional air conditioning comes with rising energy use and environmental costs. The solution lies in efficient, sustainable cooling alternatives. This article explains why cooling demand is rising, what environmentally responsible options exist, how climate and building type affect performance and how solutions - many offered by Daikin - help deliver comfort, health and efficiency without increasing the climate burden.

Why has cooling become a necessity, not a luxury?

As temperatures continue to rise, extreme heat is increasingly affecting people’s health and comfort. At Daikin, we believe that technology and care go hand in hand. By developing energy-efficient cooling and heating solutions, we’re helping communities adapt to these changing conditions, creating safer, more comfortable environments for everyone.

In the UK, with temperatures rising and heatwaves becoming more frequent demand for domestic cooling is increasing.  When paired with cleaner energy – cooling has become a key part of many people's climate resilience strategies. Yet this rising demand for traditional air conditioning systems comes at a steep environmental cost.

As of 2022, space cooling - including air-to-air heat pumps and fans - accounts for about 7% of global electricity consumption and approximately 3% of energy related CO₂ emissions, rising to 3.2% of total greenhouse gases when the potent refrigerants (HFCs) are included. You may want to explore alternatives to traditional AC units, and here's why:

The questions over traditional AC units

Conventional air conditioners consume substantial amounts of electricity – globally accounting for roughly 7% of power usage – with projections suggesting this could triple by 2050 if no changes occur . There are also some long-standing concerns around installation, maintenance and cost. Ultimately, though, comfort level temperature is becoming a must, this is why alternative heating and cooling approaches, as those championed by Daikin, are gaining momentum.

What alternatives to traditional air conditioning are available?

Alternative cooling systems offer environmentally friendly and accessible options for maintaining comfort. These solutions come in several forms:

• Passive cooling: Involves architectural design strategies such as cross-ventilation, shading, reflective surfaces, and thermal mass to naturally regulate temperature. These are ideal in well-planned new constructions.
• Evaporative cooling: Some products use water to cool the air through evaporation. These are energy-efficient and work best in dry environments, offering an eco-friendly alternative to air conditioning.
• Portable air coolers: These units are compact, user-friendly, and perfect for cooling small spaces. They don’t require permanent installation, making them ideal for renters or urban dwellers.

Cooling needs differ depending on geography and building type.  This is why designing with climate context is key to long-term comfort and efficiency.

What is passive cooling and how does it work?

Passive cooling refers to design strategies that reduce indoor temperatures without mechanical systems. These principles are centuries-old and still effective today - especially when integrated into modern architecture.

At its core, passive cooling relies on elements like thermal mass (materials that absorb and release heat slowly), shading (overhangs, pergolas, or louvers), and natural airflow. Common thermal mass materials include concrete, brick, and stone, these can absorb heat during the day and release it gradually at night, helping to stabilise indoor temperatures

For instance, proper window orientation and the use of cross-ventilation can dramatically improve comfort levels without using electricity.

Simple but effective features include trees, trellises, and roof overhangs, that block direct sunlight and reduce solar heat gain.

However, passive cooling has limitations in extreme climates. In more humid environments or during heatwaves, natural ventilation alone may not suffice to maintain safe indoor temperatures.

Examples of passive cooling in practice include:

• Mediterranean homes with thick stone walls and small windows to reduce heat absorption.
• Scandinavian builds that incorporate smart airflow systems and high insulation to maximise passive thermal control.

Mechanical cooling alternatives to traditional air conditioning

For homes that need mechanical cooling support without the high energy use of conventional air conditioning, several lower-impact solutions can provide effective comfort when matched to the right climate and building type.

Attic fans

Attic fans work by ventilating hot air trapped in the attic, reducing the heat load on upper floors. By expelling hot air, they help keep indoor temperatures down, particularly during the early evening when roof heat peaks.

Climate and building considerations:

• Work best in hot, dry climates, where hot air can be expelled without adding moisture

• Can be less effective or counterproductive in humid climates, as ventilation may draw in moist air and increase indoor humidity

• In cold climates, uncontrolled use can cause unwanted heat loss in winter and increase heating demand

• Homes with poor insulation and ventilation typically see greater temperature reductions than well-insulated buildings

Costs:

• Attic fans typically cost £200–£1,200, including installation

• Operating costs are minimal, using around 50–100 watts

Evaporative (swamp) coolers

Evaporative coolers use water evaporation to lower air temperature. They are significantly more energy-efficient than compressor-based AC units and do not use harmful refrigerants.

Best suited for:

• Dry climates, where the air can absorb moisture effectively

Limitations:

• Less effective in humid regions, like the UK where moisture saturation limits evaporation

Installation and maintenance:

• Generally simple installation

• Maintenance involves cleaning filters and water tanks

Costs:

 

• Portable units start at around £100, depending on their size and feature

Portable solutions: fans, portable units, and hybrid cooling

Portable cooling solutions offer flexibility, particularly for renters, temporary setups or homes without ductwork. They are suitable for small rooms and targeted cooling.

Fans circulate air and support evaporative cooling from the skin, without lowering air temperature, while portable AC units actively remove heat and moisture.

Hybrid models combine evaporative cooling with filtration, offering a middle ground where air purification is also a concern.

These hybrid units provide energy-efficient cooling through evaporative technology—using significantly less electricity than conventional ACs—while also improving indoor air quality by filtering out pollutants, allergens, dust, and some bacteria.

Maintenance consists of draining condensation, cleaning filters, and occasional replacement of cooling pads.

Installation is typically plug-and-play, requiring a power outlet and window access where applicable.

How can cool roofs and thermal barriers reduce heat and save energy?

Cool roofs - through reflective coatings, bright membranes, or green roofing reflect solar radiation, reducing roof temperatures by up to 30 °C, and lowering cooling needs by 10-30%. When paired with proper attic insulation and ventilation, they offer excellent long-term returns. Daikin-compatible smart attic solutions complement this approach.

The installation cost of cool roofs can be quite high, however, they can save energy and money over time. Cool roof systems are suitable for both residential homes and commercial buildings, particularly in warm or sunny climates. Over time, they deliver a strong return on investment through lower air conditioning bills and extending the life of any heating, ventilation and cooling system.

Combined with passive cooling or smart automation, these solutions offer a scalable way to cut energy use and maintain thermal comfort sustainably.

How can smart home technology improve cooling efficiency?

Smart thermostats, automated blinds, and air‑quality sensors optimise thermal comfort and energy use. For example, blinds can block heat when sunlight is at its strongest, while smart controls can trigger attic fans or shades rather than relying on AC. When seamlessly integrated with passive and mechanical systems, smart tech enables responsive, efficient cooling.

Heat pumps as a dual‑purpose solution

Heat pumps provide both heating and cooling by transferring heat rather than generating it, improving efficiency compared with conventional systems.  Their environmental benefits and energy flexibility have made them a core part of Daikin’s home‑heating and cooling offerings.

Practical steps to keep homes cooler

Reducing indoor heat gain is one of the simplest and most cost-effective ways to keep a home cooler without relying heavily on mechanical systems.

Reduce internal heat sources

• Switch to LED lighting: incandescent bulbs emit up to 90% of their energy as heat
• Minimise cooking during peak hours: cook early in the morning or after sunset, or use microwaves or outdoor grills
• Manage appliance placement: keep heat-generating devices away from thermostats and from each other.

Limit solar heat gain

• Use blackout curtains and insulated window coverings to block solar radiation and retain cool air
• Apply window films or tints to reduce UV and infrared radiation while maintaining natural light

Improve airtightness and insulation

• Seal gaps and cracks around doors, windows, plumbing and outlets
• Upgrade attic insulation and air sealing, as heat often accumulates in attic spaces and radiates downward

Support airflow and ventilation

• Ventilation upgrades, such as solar-powered exhaust fans or added grilles, help remove trapped hot air
• Improved ventilation reduces pressure on fans and cooling systems

Which cooling solutions work best in different climate zones?

• In humid regions (e.g. southern UK and parts of Europe), heat pumps or AC units are advantageous because they can dehumidify the indoor air while cooling
• Arid zones: Evaporative coolers and passive methods offer efficient, low‑cost cooling.
• Urban apartments: Benefit from portable units, blinds, and smart systems.
• Detached homes: Can integrate attic fans, cool roofs, and heat pumps with smart controls.

Budget considerations: Upfront vs. long-term costs

When selecting a cooling system, both initial investment and lifetime costs must be considered. Different solutions come with varying price points, energy demands, and maintenance needs.

Cooling option	Upfront cost	Maintenance	Energy cost	Notes
Window ACs	Low	Moderate (filter cleaning, seasonal servicing)	Medium–High	Effective for single rooms; less efficient overall.
Portable units	Low–Medium	Low	Medium	Flexible but can be noisy and energy-hungry.
Swamp coolers (evaporative)	Low–Medium	Low (water refills, occasional pad replacement)	Low	Great in dry climates, not ideal in humid zones.
Heat pumps	High	Low	Low	Dual-purpose, high efficiency, often eligible for subsidies.
Cool roofs	Medium–High (£20–40/m²)	Very low	Low	Long-term ROI through passive heat rejection.
Attic fans	Low–Medium	Very low	Low	Efficient heat extraction in upper floors.

Numerous government grants and incentives are available to reduce the upfront burden of sustainable solutions. 

In England and Wales, the Boiler Upgrade Scheme (BUS) is a UK Government incentive that has been extended to 2030 and helps homeowners switch to low-carbon heating. 

The scheme supports both air-to-water (A2W) and air-to-air (A2A) heat pumps installed for space heating. Homeowners can receive £7,500 towards an A2W heat pump. A £2,500 grant for A2A heat pumps is expected to come into effect during 2026. 

Homeowners in Scotland can apply for a standalone grant of £7,500 from the Home Energy Scotland Scheme to install heat pumps. Previously, applicants were required to sign up for a loan before they qualified for this funding, but they can now access the money directly. The enhanced measures will also include an extra £1,500 for homeowners in rural areas. A standalone grant of £7,500 for energy efficiency improvements to homes is also available. 

To help make your money go further, the Government doesn’t charge VAT on the installation of air source heat pumps. You might also be eligible for a free heat pump and/or a range of energy-saving products under the Energy Company Obligation Scheme. Further details of this can be found on the Gov.UK website or from your energy company.

How can cooling be effective without harming the environment?

As global demand for cooling increases, so does its environmental footprint—unless we make intentional, informed choices.

Traditional air conditioners are responsible for a growing share of global electricity use and emissions. Evaporative coolers, on the other hand, use up to 75% less energy and have a lower environmental impact—though they’re only effective in dry climates.

Traditional air conditioners rely on compressor-based refrigeration cycles that consume significant electricity, making them responsible for a growing share of global energy use and CO₂ emissions.

Heat pumps, that provide both heating and cooling by transferring heat rather than generating it, are much more energy-efficient. When paired with renewable electricity, they can reduce CO₂ emissions by up to 60% compared to traditional systems.

Sustainable cooling solutions for health, comfort and the future

As cooling becomes increasingly essential in a warming climate, the challenge is to maintain comfort without increasing energy use or environmental impact. The most effective cooling alternatives combine passive design, smart controls and energy-efficient systems such as heat pumps, adapted to local climate and building type. By lowering energy demand while protecting health and indoor comfort, sustainable cooling solutions offer a practical and future-proof path forward. Daikin’s approach focuses on responsible cooling that strengthens resilience today and for the long term.

Key takeaways

• Cooling is a health necessity, not a luxury, as heatwaves intensify across Europe.

• Traditional air conditioning increases energy use and emissions, making efficient alternatives essential.

• Climate-appropriate solutions matter: passive and evaporative cooling suit dry regions, while heat pumps perform best in mixed and humid climates.

• Smart technologies reduce cooling demand by optimising shading, ventilation and system use before AC is needed.
• Energy-efficient heat pumps provide long-term comfort with lower emissions, especially when paired with renewable energy.