Clean Energy vs. Nuclear ETFs by the Numbers: Assets, Fees and Flows

By Adam Patti, Chief Executive Officer, VistaShares | Published November 13, 2026

Clean energy ETFs and nuclear ETFs both offer exposure to low-carbon power, but they hold very different companies. Clean energy funds hold solar, wind, hydrogen and fuel cell businesses; nuclear funds hold uranium miners, reactor builders and the utilities that run nuclear plants. In the numbers, nuclear funds are fewer but larger, while clean energy funds are more numerous and drew new money recently. This page compares the two with dated figures.

Figure	Clean energy ETFs	Nuclear and uranium ETFs
Funds tracked by ETFIQ (Nov 12, 2026)	16	10
Combined net assets (Nov 12, 2026)	$5.0 billion	$10.5 billion
Largest single fund, net assets (Nov 11 to 12, 2026)	$2.1 billion	$4.7 billion
Fee range, lowest to highest (Nov 11 to 12, 2026)	0.35% to 0.79%	0.35% to 0.85%
Typical fund’s weight in S&P 500 stocks (Nov 12, 2026)	9%, 49th highest of 54 themes	16%, 42nd highest of 54 themes
Different companies among the funds’ ten largest holdings (holdings Jun 30 to Nov 12, 2026)	128, across 16 funds	75, across 10 funds
Net flows, month to Nov 11, 2026	$165 million in, 12 of 16 funds counted	$132 million out, 4 of 10 funds counted
Net flows, week to Nov 11, 2026	$170 million in, 11 of 16 funds counted	$67.2 million out, 3 of 10 funds counted

Sources: ETFIQ clean energy ETFs and ETFIQ nuclear and uranium ETFs, data as of Nov 12, 2026, holdings filed Jun 30 to Nov 12, 2026, flows as of Nov 11, 2026. Flows count only funds with daily share data.

What do these two themes hold?

ETFIQ describes clean energy ETFs as funds that hold solar, wind, hydrogen and fuel cell companies, and the utilities and equipment makers behind them. It describes nuclear ETFs as funds that hold uranium miners, reactor builders and the utilities that run nuclear plants.

ETFIQ puts uranium funds and nuclear reactor funds in one category because their portfolios overlap: the largest holding of the reactor funds and of the uranium funds is the same company. That makes this group less varied than its two labels suggest. Our article on gas, nuclear and small modular reactors explains why nuclear power has drawn new attention, and AI power and electrification covers the demand behind it.

How many funds are there, and how large?

ETFIQ tracked 16 clean energy ETFs holding a combined $5.0 billion and 10 nuclear and uranium ETFs holding $10.5 billion as of November 12, 2026. With fewer funds, the nuclear group holds about twice the assets. Its largest fund held $4.7 billion, against $2.1 billion for the largest clean energy fund.

Both groups are small next to the largest themes. ETFIQ counted 428 thematic ETFs across 55 themes on November 12, 2026, and the largest thematic fund held $65.1 billion. Small funds can trade with wider spreads, and our article on bid-ask spreads, premiums and discounts explains what to watch.

How do fees compare?

Fees in the two groups were close. Clean energy ETFs ran from 0.35% to 0.79% and nuclear and uranium ETFs from 0.35% to 0.85%, as of November 11 to 12, 2026. Both ranges sit well above the 0.14% asset-weighted average that ICI reported for index equity ETFs in 2025, which reflects the narrower focus and smaller size of most thematic funds.¹

How much do these funds overlap with the S&P 500?

Very little, in both cases. The typical clean energy ETF carried 9% of its weight in S&P 500 stocks, the 49th highest of 54 themes with holdings on file. The typical nuclear ETF carried 16%, the 42nd highest. Many of the companies in both groups are listed outside the U.S. or are too small for the index, such as uranium miners and component makers.

Low overlap means these funds add exposure that a broad U.S. index fund does not already hold. It also means their results can differ sharply from the broad market, in either direction.

How many companies do they hold?

Across their ten largest holdings, the 16 clean energy ETFs named 128 different companies, and the 10 nuclear ETFs named 75, by holdings dated June 30 to November 12, 2026. Clean energy is the broader theme, spanning several technologies. Nuclear funds draw on a smaller set of miners, fuel processors, reactor builders and utilities, so the same names recur from fund to fund. Our article on ETF concentration risk explains why a narrow set of holdings matters.

Where has money been flowing?

The two themes moved in opposite directions. In the month to November 11, 2026, clean energy ETFs took in a net $165 million across 12 of 16 funds with daily data, and nuclear ETFs had a net outflow of $132 million across 4 of 10 funds. In the week to the same date, clean energy funds took in $170 million and nuclear funds lost $67.2 million. Only a minority of nuclear funds publish daily share data, so that figure is a partial count. The full ranking is on ETFIQ’s theme flows page.

How should investors use these numbers?

Look past the label: clean energy and nuclear funds both relate to low-carbon power, but they hold different businesses with different drivers, from commodity prices for uranium to subsidy and interest rate sensitivity for renewables.

Expect volatility: narrow themes with low S&P 500 overlap can move much more than the broad market.

Date every figure: theme flows can reverse within weeks. Our guide on how to evaluate a thematic ETF lists what else to check. More thematic articles are in the Thematic ETF Guide.

Frequently asked questions

How many nuclear ETFs are there?

ETFIQ tracked 10 U.S. listed nuclear and uranium ETFs on November 12, 2026, holding a combined $10.5 billion.

How many clean energy ETFs are there?

ETFIQ tracked 16 U.S. listed clean energy ETFs on November 12, 2026, holding a combined $5.0 billion.

Why are uranium and nuclear ETFs counted together?

Their portfolios overlap heavily. ETFIQ found that the largest holding of the reactor funds and of the uranium funds is the same company.

Do clean energy ETFs hold nuclear companies?

Not as a focus. ETFIQ defines clean energy funds by their solar, wind, hydrogen and fuel cell holdings, and the utilities and equipment makers behind them.

Which theme overlaps less with the S&P 500?

Clean energy. The typical fund carried 9% of its weight in S&P 500 stocks, against 16% for nuclear funds, as of November 12, 2026.

Which took in more money recently?

Clean energy ETFs took in $165 million in the month to November 11, 2026, while nuclear ETFs had a net outflow of $132 million, counting only funds with daily share data.

Adam Patti, Chief Executive Officer of VistaShares, is also the founder of ETFIQ. ETFIQ does not accept payment from ETF issuers, and its figures are calculated from public filings and market data.

Cite this page: Adam Patti, "Clean Energy vs. Nuclear ETFs by the Numbers: Assets, Fees and Flows," VistaShares, updated November 13, 2026, https://www.vistashares.com/clean-energy-vs-nuclear-etfs-by-the-numbers/. Plain-text version.

This material is provided for educational purposes only. It is not investment, legal or tax advice, and it is not a recommendation or an offer to buy or sell any security. Information is drawn from sources believed to be reliable as of the date of publication, is not guaranteed as to accuracy or completeness, and may change without notice. Figures attributed to third parties are their estimates. Projections and forecasts are not guarantees of future results. Investors should consult their own financial, legal and tax professionals before making investment decisions. Investments involve risk, including possible loss of principal. Strategies that use options involve additional risks, including limited participation in market gains, the risk that options do not perform as intended, and changes in distributions. Tax treatment depends on individual circumstances and on current law, which may change.

Investors should consider the investment objectives, risks, charges and expenses carefully before investing. For a prospectus or summary prospectus with this and other information about the Fund, please call (844) 875-2288 or visit www.VistaShares.com. Read the prospectus or summary prospectus carefully before investing.

Foreside Fund Services, LLC, distributor.