Facility Changes That Drive 80% of Emissions Savings

The overlooked 20% of building strategies can deliver 80% of emissions savings. Here’s how to reset your 2026 baseline.

Ava Montini

Jan 6, 2026

Written by

Published on

The 80/20 Pattern in Building Decarbonization

In business, the Pareto principle (the idea that 20% of actions create 80% of results) shows up everywhere. It also applies to the way buildings decarbonize.

Most portfolios still treat carbon reduction as a capital-projects problem: new chillers, new boilers, new equipment. These projects are visible, expensive, and easy to headline in ESG reports. But in practice, the biggest near-term gains lie in the systems that are already running every hour of every day.

According to the U.S. Energy Information Administration, space heating, cooling, and ventilation are among the top energy end-uses in commercial buildings, with ventilation alone consuming nearly 10% of the total building energy. Factor in heating and cooling, and the air systems you already own set the floor for your emissions profile. Industry surveys and guidance reinforce this point: HVAC systems consistently account for approximately 40% of energy use in commercial facilities. A share that shifts by climate zone but remains dominant across the board.

Before you buy new megawatts, make the watts you already use travel a shorter, smarter, more efficient path.

Filtration as a carbon multiplier (not a consumable line item)

Why filtration matters for energy (and CO₂e)

Filters impose a pressure drop; fans work against that resistance. Basic fan/affinity laws tell us that pressure rises with the square of fan speed, and fan power typically scales with pressure/flow requirements. Therefore, adding resistance increases fan energy unless the system compensates by reducing the flow.

On variable-speed systems that maintain flow, peer-reviewed work shows roughly linear fan-power response to added system pressure: a 10% rise in total pressure drop ≈ 10% rise in fan electric power (assumes fan and motor efficiencies roughly constant at operating point). CaEE

Field and lab studies show that higher filter resistance reduces supply airflow and can increase total power (especially as filters load), degrading cooling capacity and forcing longer runtimes. Newer research also documents the compounding effects of filter loading, with heavy clogging cutting net supply airflow by >30%, a textbook example of invisible energy waste. ScienceDirect

Moving up in MERV doesn’t automatically mean higher energy costs. Well-designed filters use optimized media and geometry (like deeper pleats or more surface area) to keep airflow resistance low. Studies have shown that these higher-efficiency filters can have a lower pressure drop than inexpensive MERV 8 pleated filters, especially when systems are properly balanced. In other words, it’s the filter’s pressure profile that matters, not just the MERV number. ScienceDirect

If you can lower your filter pressure drop while maintaining or improving capture, you directly reduce continuous fan energy. One of the few all-hours loads in many facilities. Because fans run whenever you condition or ventilate space, these savings translate cleanly into CO₂e reductions (see Section 5 for the math).

Demand-Controlled Ventilation (DCV)

What DCV does

It modulates outside-air intake based on occupancy (CO₂, people-count, scheduling) to avoid conditioning empty spaces. Codes and standards increasingly require or encourage DCV in high-occupancy areas, with ASHRAE 62.1 updates clarifying when and how ventilation turndown is permitted (including addenda that allow reduction to zero OA during verified unoccupied periods in certain space types). ASHRAE

Across building types and climates, published work shows that DCV control logic achieves ~9–33% HVAC energy savings. Advanced rooftop-unit control packages, which incorporate multi-speed/variable fans, DCV, and smarter economizer control, have delivered double-digit fan and cooling savings, sometimes exceeding 20%. Taylor & Francis Online

Lawrence Berkeley National Laboratory (LBNL) analyses flag that cost-effectiveness depends on the baseline over-ventilation and occupancy patterns; if your current minimums are already close to code, savings shrink. That’s a guidance feature, not a flaw—the point is to measure your baseline VRs before projecting benefits. Energy Technologies Area

DCV is a surgical lever: attack over-ventilation where it exists, prove reductions with trend data, and lock in permanent load reductions; especially valuable in heating-dominated regions where conditioning outside air is expensive in both energy and CO₂e. Energy Codes Guide

Preventative Maintenance

Controls drift, coils foul, dampers stick, sensors mis-calibrate—quietly taxing 5–15% of portfolio energy in many studies. Modern fault detection & diagnostics (FDD) tools and structured maintenance programs quickly recapture that waste. NREL Docs

Coil fouling: Government and academic sources document material energy penalties from dirty coils; some guidance cites compressor energy up to ~30% higher with fouled condensers (case and climate dependent). Even conservative findings confirm meaningful efficiency and capacity degradation. Avoidable with routine cleaning. Energy.gov.au
Economizers & OA paths: Mis-tuned economizers are common and costly; retuning and sensor QA via FDD is repeatedly highlighted in DOE/NREL/PNNL guidance as a top-tier low-cost fix. PNNL
RTU controls refresh: Campaign results and tech briefs demonstrate that advanced RTU control (variable fan, DCV, and economizer optimization) consistently yields energy reductions of more than 20%, with 25–50% reductions cited in certain deployments compared to legacy constant-speed, always-open baselines. Better Buildings Solution Center

Maintenance is mitigation. It’s also Scope 3-friendly: operating equipment at design efficiency extends service life and defers replacements, reducing embodied carbon churn in your capital plan. (See the measurement plan below to make these savings auditable.)

Turning kWh into CO₂e: a quick, defensible method

Your sustainability stakeholders care about tons, not watts. To translate HVAC savings into CO₂e:

Quantify energy from the measure (e.g., fan kWh drop from low-pressure filters; heating/cooling kWh or therms saved from DCV; kWh saved from FDD fixes).
Apply grid or fuel emission factors appropriate to the site(s) and year.
- U.S. electricity (2022 eGRID avg): ≈ 0.393 kg CO₂/kWh (867.5 lb/MWh delivered). US EPA+1
- Canada electricity (2025 factors) vary widely by province—e.g., Ontario: 38 g CO₂e/kWh; Alberta: 490 g CO₂e/kWh. Selecting the right regional factor matters. Canada.ca

If a low-pressure filter reduces fan energy by ~300 kWh/year per unit (magnitude depends on hours, fan size, and baseline pressure):

U.S. eGRID avg: 300 kWh × 0.393 kg/kWh ≈ 118 kg CO₂e/year per filter.
Ontario: 300 kWh × 0.038 kg/kWh ≈ 11 kg CO₂e/year per filter.

This is why portfolios across different grids see very different CO₂e per kWh outcomes. Even when the kWh savings are identical. US EPA

For transparency in ESG filings, reference the EPA eGRID subregion or the Government of Canada tables (or your utility-specific factors) and archive the PDFs used for each reporting year. US EPA

Risk management & IAQ alignment

Stay within ASHRAE 62.1 minimums at all times when spaces are occupied. DCV is about right-sizing, not starving air. Updated addenda clarify occupancy-based turndown rules—use them. ASHRAE
Filter choices: Seek equal or higher capture with lower ΔP; measure clean and loaded ΔP at your own face velocities. Research shows energy impact depends on filter design and system configuration, not only MERV. ScienceDirect
Measurement culture: Treat IAQ and energy as co-optimized objectives by trending PM, CO₂, temperature, and fan power together, so nobody is flying blind.

What this unlocks for 2026 capex

Once you bank the operational tons above, the economics of electrification, heat recovery, and heat pumps improve because you’re sizing for reduced loads. DOE/NREL work on advanced RTU control consistently shows meaningful kWh reductions when variable fans and DCV are layered in—think of these as pre-project multipliers that de-risk later capex. NREL Docs

The Power of the Overlooked 20%

In the rush to decarbonize, it’s tempting to chase the biggest, newest technologies. But the truth is that many of the most reliable carbon savings are already within reach. Hidden in fans, filters, ventilation rates, and maintenance routines.

Filtration, demand-controlled ventilation, and preventative maintenance may not make the headlines, but together they represent the overlooked 20% of actions that can deliver 80% of your emissions savings. They are measurable, repeatable, and scalable across portfolios, exactly the kind of solutions facility leaders need as they enter a new year of climate commitments.

What is Green Finance? And How it Can Benefit Your Business

Jennifer Crowley
Aug 2, 2023
3 min read

Updated: Jul 19, 2024

Leaf cutting growing from a pile of coins atop a wooden table — Green financing broadens access to environmentally-friendly goods and services for individuals and enterprises, equalizing the transition to a low-carbon society and resulting in more socially inclusive growth.

Green finance is a loan or investment that promotes environmentally-positive activities, such as purchasing ecologically-friendly goods and services or constructing green infrastructure. As the hazards connected to ecologically destructive products and services rise, green finance is becoming a mainstream phenomenon.

What is the Benefit of Green Financing?

Green financing broadens access to environmentally-friendly goods and services for individuals and enterprises, equalizing the transition to a low-carbon society and resulting in more socially inclusive growth. This results in a ‘great green multiplier’ effect in which both the economy and the environment gain, making it a win-win situation for everyone.

Environmental Impact

a. Climate Change Mitigation: Green financing plays a crucial role in funding projects that help mitigate climate change, such as renewable energy generation, energy-efficient technologies, and carbon capture and storage. By supporting these initiatives, green financing contributes to reducing greenhouse gas emissions and transitioning to a low-carbon economy.

b. Conservation of Natural Resources: Green financing supports projects aimed at preserving and restoring ecosystems, protecting biodiversity, and promoting sustainable agriculture and forestry. These initiatives help conserve natural resources, enhance biodiversity, and promote sustainable land and water management practices.

c. Transition to a Circular Economy: Green financing encourages projects that promote the principles of a circular economy, such as recycling, waste reduction, and sustainable production practices. This shift from a linear “take-make-dispose” model to a circular approach helps reduce resource consumption, minimize waste generation, and promote sustainable consumption patterns.

Economic Advantages

a. Market Opportunities: Green financing creates new market opportunities by supporting the development and deployment of clean technologies and sustainable infrastructure. This can drive economic growth, innovation, and competitiveness, particularly in sectors such as renewable energy, green construction, and sustainable transportation.

b. Risk Mitigation: Green financing can help mitigate financial risks associated with climate change, resource scarcity, and environmental regulations. By supporting projects that promote sustainability, financial institutions and investors can reduce exposure to stranded assets, regulatory penalties, and reputational risks.

c. Cost Savings: Green financing promotes energy efficiency and the use of renewable energy sources, leading to cost savings for businesses and households in the long run. Energy-efficient buildings, for example, have lower operating costs, reduced energy consumption, and increased asset value.

Social Implications

a. Job Creation: Green financing can stimulate the growth of green industries such as renewable energy, energy efficiency, and sustainable infrastructure. This can lead to the creation of new job opportunities, both directly and indirectly, contributing to economic development and reducing unemployment rates.

b. Health Benefits: Green financing promotes projects that aim to reduce pollution and improve environmental conditions. This can have positive effects on public health by decreasing air and water pollution, thereby reducing the incidence of respiratory and other environmentally-related diseases.

c. Community Development: Green financing supports projects that enhance community resilience, such as sustainable housing, clean transportation, and access to renewable energy. These initiatives can improve living conditions and promote social equity by providing affordable and sustainable solutions to communities, including those that are traditionally underserved.

Types of Green Financing

Now that we have an understanding of what green finance is, let’s explore its different types:

Green Mortgages

Lenders provide better terms to home purchasers of properties with a high environmental sustainability rating or if the buyer agrees to invest in enhancing the environmental performance of a property.

Green Loans

Green loans are used to support environmental initiatives such as household solar panels, electric automobiles, energy efficiency projects, and more.

Green Credit Cards

Often considered to be a type of credit card that donates a portion of your eligible purchases to an organization that invests in climate action and/or partners with carbon mitigation programs to help you reduce your carbon footprint.

Green credit cards such as Aspirations’ Zero card plant a tree every time a customer makes a purchase. They enable customers to direct their expenditure toward green finance to have a lasting environmental impact.

Green Banks

Green banks employ public funds to spur private investment in renewable energy and other environmentally friendly initiatives. According to a 2020 research, the number of green banks in the US increased from one to 20 between 2011 and 2020, investing $7 billion in renewable energy.

Green Bonds

Green bonds account for the vast bulk of green funding. They include bond investments, the earnings from which are used to support various green initiatives such as renewable energy, clean transportation, and conservation, among others.

Green Financing vs Sustainable Financing

Green finance is a loan or investment that promotes environmentally-positive activities, such as the purchase of ecologically-friendly goods and services or the construction of green infrastructure.

Sustainable finance is an improvement of green finance, aiming to increase long-term investments in sustainable economic activities and projects but also taking into consideration environmental, social and governance (ESG) issues and risks.

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