Scope 1, 2, and 3 Emissions Explained

Why Emission Scopes Matter for Data Interpretation

When you look up a company on PlainCarbon and see it emits 2 million metric tons of CO2e, the natural question is: is that a lot? The answer depends entirely on which emissions are being counted. The Greenhouse Gas Protocol, the global standard for corporate emissions accounting, divides emissions into three scopes, and the distinction changes everything about how you interpret the numbers.

A power plant's Scope 1 emissions are enormous because burning coal and gas produces CO2 directly on-site. But a tech company's Scope 1 might be tiny, most of their impact comes from the electricity powering their data centers (Scope 2) and the manufacturing of their hardware (Scope 3). The EPA GHGRP captures the power plant fully but misses most of the tech company's footprint.

Scope 1: Direct Emissions (What PlainCarbon Shows)

Scope 1 emissions come from sources owned or controlled by the reporting company: smokestacks, furnaces, fleet vehicles, and chemical processes. This is what the EPA GHGRP mandates for facilities above 25,000 MT CO2e/year.

What it tells you: The direct, on-site climate impact of a company's operations. For heavy industry, power generation, petroleum refining, chemicals, cement, Scope 1 is often the largest category. Search companies on PlainCarbon to see their reported Scope 1 figures.

What it does not tell you: Nothing about purchased electricity, supply chain impacts, or downstream product use. A company with low Scope 1 may still have enormous total emissions.

How to use it: Compare companies within the same industry on our rankings page. Scope 1 comparisons are most meaningful when companies operate similar types of facilities.

Scope 2 and 3: The Missing Picture

Scope 2 covers indirect emissions from purchased electricity, steam, heat, or cooling. Scope 3 covers everything else in the value chain, supplier emissions, employee commuting, product use, and end-of-life treatment.

What it tells you: The full picture. For many companies, Scope 3 dwarfs Scopes 1 and 2 combined. An automaker's factory emissions (Scope 1) are small compared to the lifetime emissions of the vehicles it sells (Scope 3).

What it does not tell you: Scope 2 and 3 are not in the EPA GHGRP data. Companies report these voluntarily through mechanisms like CDP disclosures, sustainability reports, or SEC climate filings. Quality and completeness vary enormously.

How to use it: When interpreting a company's GHGRP data on PlainCarbon, consider: is this a company whose impact is primarily direct (Scope 1) or indirect (Scope 2/3)? Power plants and refineries are Scope 1-heavy. Tech companies, retailers, and financial firms are Scope 2/3-heavy.

Common Misinterpretations of Scope Data

One of the most common errors in climate discussion is comparing companies across different sectors using only Scope 1 data. A large tech company with minimal Scope 1 may appear "green" next to a power utility, but when Scope 2 and 3 are included, the total carbon footprint may be comparable. Data centers consume enormous amounts of electricity, and the manufacturing supply chain for electronics is carbon-intensive.

Another frequent misinterpretation is equating Scope 1 reductions with genuine decarbonization. A company can reduce Scope 1 by selling its high-emitting facilities to another company, the emissions do not disappear; they simply move to a different corporate owner. This is why facility-level trend analysis on PlainCarbon is valuable: it tracks emissions at the physical source, not just the corporate reporting entity.

What This Means for You: A Practical Framework

Step 1, Look up the company on PlainCarbon. Check their company page for Scope 1 emissions, facility count, industry, and trend.

Step 2, Identify the industry context. Heavy industry (power, oil, chemicals) = Scope 1 is highly meaningful. Services/tech = Scope 1 is a small fraction of total impact.

Step 3, Check for voluntary disclosures. For a fuller picture, look for the company's CDP report or sustainability report, which may include Scope 2 and 3.

Step 4, Compare within sectors. Use PlainCarbon's rankings to compare companies in the same industry, that's where Scope 1 comparisons are most valid and informative.

Frequently Asked Questions

What are Scope 1, 2, and 3 emissions?

Scope 1 covers direct emissions from owned or controlled sources (e.g., smokestacks, fleet vehicles). Scope 2 covers indirect emissions from purchased electricity, heat, or steam. Scope 3 covers all other indirect emissions in the value chain, including suppliers and product use. The EPA GHGRP tracks Scope 1 only.

Why does PlainCarbon only show Scope 1 emissions?

PlainCarbon uses EPA GHGRP data, which mandates reporting of direct (Scope 1) emissions from facilities emitting 25,000+ metric tons CO2e per year. Scope 2 and 3 are not covered by this program. For full corporate emissions profiles, check company sustainability reports or CDP disclosures.

How much of total US emissions does the EPA GHGRP capture?

The GHGRP covers approximately 85% of total US greenhouse gas emissions from roughly 8,737 reporting facilities. The remaining 15% comes from smaller facilities below the 25,000 MT threshold and sectors not covered by the program.

Are Scope 3 emissions larger than Scope 1?

For most companies, yes, often by a factor of 5-10x or more. A fossil fuel company may have moderate Scope 1 emissions from extraction but enormous Scope 3 emissions from customers burning the fuel. Understanding this context is essential when interpreting GHGRP data.