You build the plant once, then sell the same electricity for thirty years. The whole game is who pays you, and how sure that payment is.
A power company spends an enormous amount of money up front to build something that makes electricity: a coal plant, a wind farm, a solar field, a dam. Then, for the next twenty or thirty years, it sells the electricity that thing produces. So the business is not really about this year's sales. It is about a giant asset built with borrowed money, and the long, steady stream of payments it throws off, if the people buying the power actually pay on time. The sections below explain how electricity gets from a plant to your home, why the same industry contains completely different kinds of businesses, and where the money quietly goes missing.
Answer these six and you have understood the industry. The rest of the page is the detail behind them.
Power is not one business. It is three, bolted together in a chain, and each link makes money differently.
Someone has to actually produce the power. That is generation: a coal or gas plant burning fuel, a dam letting water fall, a wind farm, a solar field. This is the most capital-heavy step. You spend thousands of crores building the plant, and only then does it start producing anything to sell. Generators are the factories of the power world.
The electricity then has to travel, often hundreds of kilometres, from where it is made to where it is used. That job, the high-voltage highways of wires and towers, is transmission. A transmission company does not make or sell electricity. It owns the wires and charges a fixed fee for letting power flow through them, like a toll road for electrons.
Finally, the power has to be split up and delivered to millions of homes, shops and factories, and billed to each one. That last mile is distribution, run mostly by state-owned bodies called DISCOMs (distribution companies). Remember this word. The DISCOM is the one who actually collects your electricity bill, and, as you will see, the DISCOM is where the whole industry's money gets stuck.
The word "power" hides two opposite animals. One is boring and safe. The other is a gamble. Confusing them is the most common beginner mistake.
Most of India's big power assets earn a return that a regulator sets in advance. The deal is simple: the company invests the capital, and the regulator lets it earn a fixed percentage on that money, year after year, almost regardless of what happens. This is boring by design, and boring is the point. The profit is predictable, the cash is steady, and the risk is low, because the return is written into the rules.
The other kind does not have a guaranteed buyer or a fixed return. It produces electricity and sells it into the open market at whatever price it can get that day, like a farmer taking vegetables to a market where the price swings hour to hour. When power is scarce, prices spike and merchant players make a killing. When there is a glut, prices crash and they can lose money. Same plant, wildly different fortunes, depending entirely on the market.
This single question separates a safe power company from a risky one. If most of the electricity is sold under long, fixed contracts to reliable buyers, the future is visible and the earnings are steady. If a lot of it is sold merchant, into the open market, the earnings will lurch around and you are really betting on power prices. Two companies can own identical plants and be completely different investments, purely because of who has promised to buy their output.
In power, the most important document is not the balance sheet. It is a signed promise to buy the electricity for the next twenty-five years.
A Power Purchase Agreement, or PPA, is a long contract where a buyer agrees to buy a plant's electricity, usually at a fixed price, for a very long time, often twenty-five years. This is the foundation of the whole business. Before a company builds a giant solar or wind plant, it wants a PPA in hand, because that signed promise is what turns a risky construction project into a predictable, decades-long stream of income. No PPA, and the plant is a gamble on prices. With a PPA, it is an annuity.
The fixed price cuts both ways. It protects the company when market prices fall, because it still gets its agreed rate. But it also caps the upside, because if power prices soar, the company is stuck selling cheap under the old contract. A PPA trades away the thrill of high prices for the safety of a known one. For most utilities that is a good trade, and it is exactly why their earnings are so stable and so dull.
You built the asset. Now the only question is how hard it works. One ratio captures it.
A power plant has a maximum it could produce if it ran flat out every hour of the year. What it actually produces is almost always less. The share of its full capacity that a plant genuinely delivers over a year is called the Plant Load Factor, or PLF. It is simply how busy the machine is. Because the cost of building the plant is fixed whether it runs a lot or a little, a higher PLF spreads that cost over more electricity and makes each unit far more profitable.
Here is a trap beginners fall into. A solar plant only makes power when the sun shines, and a wind farm only when the wind blows. So their PLF is naturally low, often just 20-25% for solar, because the sun is down half the day and weak the rest. That is not a sign of a bad plant. It is the nature of the fuel. You must judge each type of plant against what is normal for its kind, not compare a solar farm's PLF to a coal plant's and call it broken.
This is the one thing that has broken more power companies than anything else. If you learn only one section, learn this.
Remember the DISCOMs, the state bodies that sell power to homes and collect the bills. Most of them are in deep financial trouble. They are often forced to sell electricity below what it costs them, to farmers and households, for political reasons, so they lose money on every unit. And because they are broke, they pay the generators who supplied them slowly, or late, or not fully. So a generator can produce the power, deliver it, book the sale as revenue, and then wait months or years to actually be paid.
This is why you can never trust a power company's profit line on its own. Rising reported profit means little if the cash is trapped in unpaid bills from broke DISCOMs. You have to check whether the sales are actually turning into money in the bank, or just swelling a pile of receivables (bills raised but not yet collected). A company selling mostly to strong, paying buyers is far safer than one whose reported profits are really just IOUs from bankrupt state utilities.
Power is built with borrowed money on a scale that would sink most businesses. Understanding that debt is understanding the risk.
Building a power plant costs so much that companies fund most of it with long-term loans, repaid slowly over the twenty or thirty years the asset earns. So heavy debt is not automatically a warning sign in power the way it would be for a shampoo maker. It is how the industry is built. The real question is not whether the debt is large, but whether the asset reliably throws off enough steady cash to service it.
The danger comes when the steady cash falters while the debt does not. If a DISCOM stops paying, or power prices crash for a merchant player, or a plant runs far below its expected PLF, the income shrinks, but the interest bill arrives every single month regardless. That gap, cash drying up while debt keeps demanding to be paid, is what has killed power companies again and again. A business that looked fine while the cash flowed can be fighting for survival within a year or two once it stops.
The whole sector is being remade around renewables. Two forces drive the shares from here.
India is building enormous amounts of solar and wind and, slowly, leaning away from new coal. This is reshaping the sector. Renewable power is now often the cheapest to produce, which is a real advantage, but it comes with its own headaches: it only flows when the sun or wind cooperates, so it needs storage and grid upgrades to be reliable. The winners will be the companies that can build renewables cheaply, sign solid PPAs for them, and manage the debt without over-reaching.
Because so much of power is regulated, contracted through state auctions, and steered by national targets, government policy is the biggest force over the sector. Renewable auction volumes, tariff rules, DISCOM reforms and green energy targets can lift or sink the whole industry together. Alongside policy, watch how much new capacity a company is adding, because capacity added today under good PPAs becomes the earnings of five years from now.
The risks are specific, so the windows you look through are specific too. A plain profit multiple will mislead you here.
Because reported profit can run far ahead of collected cash, and because debt is huge by design, you judge a power company through a different set of windows than a normal business.
Together these tell you whether the earnings are contracted or a gamble, whether the plant is working hard, whether the profit is real cash or IOUs, and whether the debt is safe, which is exactly what a single profit multiple cannot show you in power.
Every sector reduces to a demand metric, a pricing metric, an efficiency metric, a capital metric, and a risk metric. For power & energy, these are the ones that matter.
What each number tells you, and how to read it.
| Metric | Why it matters |
|---|---|
| Plant Load Factor (PLF) | How much of full capacity a plant actually delivers. Fixed build cost spread over more output, so higher PLF means more profit per unit. Judge each fuel against its own norm (coal 60-85%, solar 20-25%). |
| PPA Coverage | Share of output sold under long fixed contracts versus merchant. High coverage means visible, bond-like earnings; heavy merchant exposure means you are betting on volatile power prices. |
| Regulated Return on Equity | For regulated assets, the fixed percentage the regulator allows on invested capital, around the mid-teens. Makes earnings predictable regardless of demand. |
| Receivable Days | How long the company waits to be paid, mostly by cash-strapped DISCOMs. Rising receivables mean reported profit is really unpaid IOUs, not collected cash. |
| Capacity Added (MW/GW) | New generating capacity built and contracted. Capacity added today under good PPAs becomes the earnings of 4-5 years out; the sector's growth pipeline. |
| Debt / EBITDA | Power is built on heavy long-term debt by design. Large is normal; the real test is whether steady operating cash comfortably covers the interest. |
| EV/EBITDA | Counts debt alongside equity, essential in a high-debt, capital-heavy sector. Fits these asset-heavy businesses far better than plain PE. |
| Government / Policy Cycle | Renewable auction volumes, tariff rules, DISCOM reforms and green targets steer the whole sector. Policy is the single biggest external driver. |
A power company builds an asset once and sells its output for decades, and everything hinges on whether the buyer actually pays.