AES vs RUN: Which Is the Better Buy in 2026?
Last updated October 2026
Short answer
AES is the larger of the two ($10.66B market cap): the incumbent the market prices for continued execution (6.30x forward earnings, beta 0.95). RUN is the smaller challenger ($1.76B), actually pricier on forward earnings (14.07x): more room to run, but more to prove. The real question is which set of drivers you believe, and whether owning one (or both) leaves you over-concentrated.
AES vs RUN: the tie-breaker metrics
Same yardstick, side by side (as of October 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.
| Metric | AES | RUN | What it tells you |
|---|---|---|---|
| Market cap | $10.66B | $1.76B | Size. The larger name is the incumbent; the smaller has more room to grow and more to prove. |
| Forward P/E | 6.30 | 14.07 | Valuation on next year's expected earnings, the same yardstick for both. Lower is cheaper for that growth; higher means the market is paying up. |
| Trailing P/E | 5.60 | 4.93 | Valuation on the last 12 months. A big drop from trailing to forward means the market expects earnings to jump, so more growth is already in the price. |
| Beta | 0.95 | 2.43 | Volatility vs the market. Above 1 swings harder than the index; below 1 is steadier. Higher beta means bigger drawdowns to hold through. |
| Price vs 52-week range | 39% of range | 1% of range | Where today's price sits between the 52-week low and high. Near the high is momentum with less margin of safety; near the low is out of favor or a discount, depending on why. |
| Price / book | 2.16 | 0.50 | How much you pay over book value. Very high can signal an asset-light, high-return business or a rich price. |
Reading it: AES is the cheaper of the two on forward earnings, but cheaper is not the same as better. Pair the valuation with growth (how far the forward P/E sits below the trailing P/E) and risk (beta) before you decide.
Before you buy: how AES and RUN affect your concentration
The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. AES and RUN share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.
This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined AES and RUN exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.
What does The AES Corporation (AES) do?
The AES Corporation is a global electricity company that operates across four segments: Renewables, Utilities, Energy Infrastructure, and New Energy Technologies. It owns or operates a generation fleet of roughly 34,740 megawatts spanning solar, wind, hydro, energy storage, gas, and legacy coal, and it distributes power to about 2.7 million utility customers. A key growth engine has been its renewables development pipeline, with a signed power purchase agreement backlog of about 12.6 gigawatts (around 5.6 GW under construction) as of March 2026, much of it tied to surging electricity demand from AI and cloud data centers. The company has been executing a coal exit while leaning into contracted clean generation and its regulated US utilities.
What does Sunrun (RUN) do?
Sunrun (RUN) is the largest residential solar company in the United States. It designs, installs, finances, and services rooftop solar panel systems and home battery storage for homeowners. Its core model is not selling panels outright but offering solar as a service: customers sign long-term leases or power purchase agreements (PPAs) and pay little or nothing upfront, while Sunrun owns the system and collects recurring payments over 20-plus years. This builds a large, contracted base of future cash flows.
AES vs RUN: how do they differ?
Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.
- AES drivers: Pending $15.00 cash acquisition; Renewables backlog and data-center demand.
- RUN drivers: Storage attach rates; Recurring subscriber base.
Which fits which kind of investor
A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: The largest risk is deal-specific: a delay, regulatory block, or renegotiation of the $15.00 cash acquisition would remove the price support the stock currently enjoys. For RUN, sunrun is highly sensitive to interest rates because its model depends on financing long-term contracts; higher rates raise its cost of capital and compress the value of future cash flows.
AES or RUN: which should you pick?
Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick AES if you believe its drivers more; RUN if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the AES and RUN guides.
AES vs RUN: the full fundamentals
AES. AES trades at the $15.00 cash offer less a few cents, so headline multiples (a trailing P/E near 5.6 and a forward P/E near 6.3) matter less than the fixed deal price and the odds and timing of a close. With CFIUS, Ohio and European Commission approvals received by October 16, 2026, the spread has narrowed to about 0.2%. The high debt load, roughly $33 billion, is typical of a capital-intensive utility and is why the enterprise value (around $33 billion) is far larger than the equity value.
RUN. Sunrun is valued on the long-term contracted value of its subscriber base and its storage and grid-services optionality rather than current GAAP earnings. After a roughly 61% fall in 2026 the shares trade at about half of sales and half of book value, yet the market is discounting about $15.2 billion of debt, negative free cash flow and forecasts for lower earnings in 2027. Q3 2026 results on November 4 (consensus EPS about $0.32 on about $820 million of revenue) are the next data point.
Headline figures (approximate, October 2026): AES shows share price / market cap ~$14.97 (Oct 16, 2026), ~$10.7B, acquisition price $15.00/share cash; spread ~3 cents (~0.2%), revenue (ttm) ~$13.1B; Q2 2026 ~$3.42B, net income (ttm) ~$1.9B, EPS ~$2.67; Q2 2026 EPS $0.44 vs ~$0.47 consensus; RUN shows revenue (ttm) ~$3.5 billion, q2 2026 revenue (yoy) ~$870 million (+53%), ~19% above estimates, net income (ttm) ~$401 million (GAAP), operating margin ~4%.
The bottom line: AES vs RUN
AES and RUN are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined AES and RUN exposure against your real portfolio. It is not an investment adviser.
Wondering how AES or RUN fits the portfolio you already own? Walnut is an AI investing app that connects your brokerage read-only and answers questions like that about your actual holdings: overlap, concentration, and how each position tracks the S&P 500. Compare the best AI portfolio analyzers or see the best AI investing apps in 2026.
Investing in The AES Corporation with AI
Connect the broker you already use and ask Walnut's AI how AES fits what you actually hold: whether you own it already through a fund, what it would do to your concentration, and how it has tracked the S&P 500. Read-only by default, and you approve anything before it reaches your broker.
FAQ
What is the difference between AES and RUN?
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The AES Corporation is a global electricity company that operates across four segments: Renewables, Utilities, Energy Infrastructure, and New Energy Technologies. Sunrun (RUN) is the largest residential solar company in the United States. They show up together because they share investment themes, but they are different businesses, so the better fit depends on which thesis you are expressing.
Is AES or RUN the better stock?
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Neither is universally better. AES is the larger incumbent; RUN is the smaller challenger and looks pricier on forward earnings. Walnut is informational, not investment advice. Compare what each does, the tie-breaker metrics above, and the risks, then decide which fits your thesis and what you already own.
Which is cheaper, AES or RUN?
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On forward P/E (as of October 2026), AES trades at 6.30x and RUN at 14.07x, so AES is the cheaper of the two on next year's expected earnings. A lower multiple is not automatically the better buy: a richer valuation can be justified by faster growth, and a lower one can reflect real risk. Weigh the multiple against how fast each business is compounding.
Should you own both AES and RUN?
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Because they share themes, owning both concentrates you in that theme. That can be intentional (a focused bet) or accidental (less diversification than it looks). Walnut can show your combined exposure across both, and whether adding either over-concentrates you, before you buy.
What are the risks of AES vs RUN?
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AES: The largest risk is deal-specific: a delay, regulatory block, or renegotiation of the $15.00 cash acquisition would remove the price support the stock currently enjoys. Several major approvals (CFIUS, Ohio state regulators and the European Commission) were in hand by October 16, 2026, but closing can still depend on other clearances across the many countries AES operates in, and the narrow spread of about 3 cents leaves holders with little cushion if anything slips. AES also carries substantial leverage, roughly $33 billion of debt against a market capitalization near $10.7 billion, which makes it sensitive to interest rates and refinancing conditions. International operations expose it to currency, political, and regulatory risk, and the ongoing coal exit and construction pipeline carry execution risk. If the deal broke, the shares could re-rate to a standalone value that may sit below the offer price; the stock traded as low as about $13.21 over the past year. RUN: Sunrun is highly sensitive to interest rates because its model depends on financing long-term contracts; higher rates raise its cost of capital and compress the value of future cash flows. It relies heavily on federal tax credits and net-metering policies, which face political and regulatory change that can sharply alter unit economics and demand. The company carries about $15.2 billion of debt (project and corporate financing) against about $726 million of cash, and free cash flow over the trailing twelve months was about negative $2 billion, so access to capital markets matters a great deal. Analysts expect earnings per share to fall from about $1.40 in 2026 to about $0.52 in 2027, so the low trailing P/E of about 5 overstates how cheap the shares look on forward numbers. Demand is cyclical and rate-sensitive, installer competition is intense, and state-level policy shifts (such as net-metering reforms) can hurt key markets. The stock is volatile and reacts strongly to rate moves and incentive headlines; it fell about 28% after a Q2 2026 beat.
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Walnut is informational, not investment advice. This page is descriptive and not a recommendation to buy or sell AES or RUN; figures are approximate and dated (as of October 2026). Verify current data before investing.