The Problem with the “Primary Energy Fallacy” – Watts Up With That?

Why this discussion matters

When we flip on a light switch, we rarely ask where that electricity actually comes from. Sunlight, wind, coal, gas, and uranium all exist in nature for free, but turning any of them into usable electricity that arrives every second of the year at the right voltage, frequency and phase is a demanding process… a service delivered to the consumer.

This is where the idea of primary energy comes in. And it’s also where a popular argument, the Primary Energy Fallacy, fails to hold up.

What primary energy actually is

Primary energy is the raw energy pulled straight from nature: coal, gas, oil, uranium, flowing water, sunlight, wind.

Electricity is secondary energy. It only exists after a long chain of processing, conversion, and delivery. Today electricity accounts for roughly 40% of global primary energy use, despite the small fraction visibly attributed to wind and solar.

Yes, wind and solar “generate” electricity directly, but what matters here is that electricity for our grids (unlike using a DC low voltage powerbank to charge a phone) has value only, and I repeat ONLY, if it can be delivered as a service that means 24/7/365, on demand, with the “correct” voltage, frequency, phase, and current. Thermal power plants inherently provide these qualities. Wind turbines and solar panels do not. For the critics, I repeat that I am speaking of electricity usable for our grids, as for any truly off-grid application you have the freedom to do as you see fit, and I am not too concerned as it is largely irrelevant in the larger scheme of things.

The Primary Energy Fallacy, in brief

The fallacy rests on two claims:

• Stated Primary Energy Fallacy 1: “The conversion of gas and coal to power results in a loss of around 60%. This means that one unit of primary energy from wind or solar, replaces two units of that of gas/coal”
• Stated Primary Energy Fallacy 2: “The conversion losses during end use in internal combustions engines ICE are also high. Electric motors are much more efficient. Most car engines ‘lose’ 70% of fuel energy, which means that one final energy unit of electricity replaces three units of gasoline/diesel”

The misunderstanding occurs in the belief that wind and solar generate electricity without any losses (a secondary or tertiary form of energy) while coal, gas, uranium may have a high energy content but have “thermal losses” ~60-70% during processing. This Primary Energy fallacy argument is used for power generation and also for internal combustion engine vehicles (ICE) in a slightly adjusted form.

At system level, which is the only level that matters when generating electricity usable for our grids, wind and solar unfortunately deliver less net usable energy per unit of primary energy invested than coal, gas, or nuclear.

“Free” resources are not free to use

Energy agencies often report wind and solar as nearly 100% efficient because they don’t include the massive upstream work required to make that electricity usable.

For example from the recent Energy Institute Report:

• Wind + solar: ~4,655 TWh of primary energy becomes ~4,623 TWh of electricity reported as nearly lossless.
• Nuclear: ~8,500 TWh of primary energy becomes ~2,800 TWh of electricity losses included.

The problem is a simple one…Wind and solar hide their losses in their supply chain and in the “ancillary systems” required to make them “useful” for our grids, such as

• 1) A vast overbuild of wind and solar to overcome the low natural capacity factor, resulting in low net load factor, as well as the intermittency and unpredictability challenges and to charge any storage
• 2) Short duration energy storage, in the form of batteries, to overcome short duration fluctuations and to balance the grid
• 3) Long duration energy storage, envisioned in the form of hydrogen, to overcome days and weeks of insufficient combined wind and solar generation
• 4) Backup thermal power stations on standby when needed, in Germany 12-20GW of gas is required by 2030, in the future this backup is supposed to run on hydrogen
• 5) A vastly more complex and larger transmission network and integration infrastructure also for “conditioning” wind and solar power

Mining, refining, manufacturing, storage systems, grid expansion, balancing systems, and short operational lifetimes to make wind and solar useful all require enormous primary energy inputs. These do not appear in the statistics.

A coal or gas plant has clear thermal losses, but it operates 30–60 years from one site. Wind and solar require continuous rebuilding and vast supporting infrastructure.

Why wind and solar require so much system support

Three physical challenges shape wind and solar output:

• Energy density, (b) Intermittency, (c) Operational Lifetime

To compensate, five major ancillary systems are required as laid out above, 1) overbuild, 2) short duration energy storage, 3) long duration energy storage, 4) backup power stations, and 5) transmission and network integration infrastructure

All five systems must be built, maintained, replaced, and powered. Their energy and material footprint is substantial and mostly absent from primary energy reporting.

Replacing one coal, gas, or nuclear plant essentially requires building five separate wind-solar-storage-grid subsystems, each with its own lifetime and cost.

How much usable energy do we really get?

A few real-world contrasts:

Solar

• Natural capacity factor: 10% in Germany; 20–25% in sunnier regions.
• Lifetime: often 12–15 years in utility practice, not 25–30.
• Overbuild requirement for long storage: in extreme cases hundreds of times existing capacity.
• Manufacturing: heavily fossil-fuel-driven.

Wind

• Natural capacity factor: ~22% global average; good sites ~35%.
• Power density: 1–2 MW per square kilometer.
• Lifetime: 10–20 years; offshore tends toward the lower end.
• Also requires fossil-powered mining and manufacturing.

Coal or Gas

• Natural Capacity factor: 98+%, limited only by demand and lower utilization.
• Lifetime: 30–60 years.
• One plant replaces the full stack of wind/solar + ancillary systems.
• Fuel must be continuously supplied, but infrastructure lasts.

Across their full lifetimes and full systems, solar and wind return far less energy for the energy invested.

Why the fallacy persists

Because wind and solar don’t show their upstream energy requirements in national statistics, they appear cleaner, simpler, and cheaper than they truly are. Policy discussions often rely on LCOE (levelized cost of electricity), which ignores system impacts, rather than FCOE (full cost of electricity), which includes the infrastructure and reliability costs that actually matter to a country.

Primary energy accounting also assumes nearly 100% system efficiency for incoming solar radiation, which obscures the resource and energy intensity needed to collect, convert, store, and condition that energy into usable power.

So what is the real takeaway?

• Every energy system demands energy, materials, money, and time before delivering useful electricity.
• Wind and solar are not “free” once you add the storage, grid upgrades, conditioning systems, and frequent rebuilds.
• Their intermittency forces the construction of far more physical infrastructure than most people realize.
• Coal, gas, and nuclear have clear conversion losses but deliver more net usable energy per unit of system investment.
• At system level, wind and solar are less primary-energy efficient, not more.
• There’s no such thing as a free kilowatt-hour…not from coal, gas, uranium, sunlight, nor wind. Nature gives us resources; turning them into dependable electricity is always costly.
• The Primary Energy Fallacy overlooks this reality, and that’s why it misleads the debate about our energy future.

Continue reading the full blog here: The problem with the “Primary Energy Fallacy”