The Impact of Tax Incentives on Carbon Intensity in Industrial Enterprises: Mediating Role of Green Technology Innovation

Imagine the economy as a giant, bustling factory floor where machines hum, smokestacks puff, and products roll off the line. This is the industrial sector, the engine that drives our modern world but also the one that burns the most fuel and leaves the biggest carbon footprint. Now, picture "carbon intensity" not as a scary monster, but as a "carbon score"—a measure of how much pollution is created for every dollar of product made. The lower the score, the cleaner the factory. Governments want these scores to drop to zero, but factories are run by people who care about profit. If cleaning up costs a fortune and the payoff is slow, factories might just keep polluting. This is where tax incentives come in. Think of them as "reward coupons" from the government. Instead of just saying "stop polluting," the government says, "If you spend money on cool new green tech, we'll give you a discount on your taxes." But here's the big question: Do these coupons actually work? And if you have two different types of coupons, do they work better together, or do they cancel each other out?

This paper dives into that exact puzzle by looking at two specific tax rewards used in China: the "R&D expense additional deduction" (a discount for spending money on research and development) and "preferential income tax" (a discount on the taxes you pay after you've made a profit). The researchers wanted to see if these rewards actually lowered the carbon scores of industrial companies. They found that both rewards do help, but they aren't equal players. The R&D discount is the star of the show, acting like a powerful magnet that pulls companies toward inventing new, cleaner ways to make things. The income tax discount helps too, but it's more like a gentle nudge. The study also discovered a secret rule: the income tax discount only really works if the company is already spending enough on research. It's like trying to start a fire with a match (the income tax reward) when you don't have any wood (the R&D spending) yet; the match just fizzles out. But once you have a pile of wood, that match can start a roaring, clean-burning fire.

The Story of the Two Tax Coupons

The researchers looked at data from over 14,000 industrial companies in China between 2016 and 2021. They treated the companies like students in a giant classroom, checking their "homework" (how much they spent on research) and their "report cards" (their carbon scores). They wanted to know: Does getting a tax break for doing research make a company cleaner? Does getting a tax break on profits do the same? And does having both make a super-clean company?

The answer is a resounding "yes," but with a twist. Both types of tax incentives successfully lowered the carbon intensity of these companies. However, the R&D expense deduction was the heavyweight champion. It was about nine times more effective at reducing carbon pollution than the income tax incentive. Why? Because the R&D deduction is like a direct ticket to the "Innovation Lab." It tells a company, "Go build a better, cleaner machine, and we'll pay for part of the cost." This pushes companies to invent new technologies that use less energy. The income tax incentive, on the other hand, is like a "Good Job" sticker given after the work is done. It rewards companies that are already profitable, but it doesn't specifically tell them how to spend that money. Some companies might take that extra cash and spend it on short-term fun projects instead of long-term green tech, which is why it's less effective on its own.

The Magic of Teamwork

Here is where it gets really interesting. The paper found that these two tax rewards aren't rivals; they are best friends. When a company gets both, they work together to create a "1+1>2" effect. It's like having a coach who gives you a new pair of running shoes (the R&D deduction) and a coach who promises you a trophy if you finish the race (the income tax incentive). The shoes help you run faster, and the trophy keeps you motivated to keep running. Together, they push the company to innovate even harder. The study showed that when these two policies are combined, they complement each other, making the reduction in carbon intensity even stronger than if you used just one.

The Secret Threshold: Why Timing Matters

The most surprising discovery in the paper is about a "threshold," or a tipping point. Imagine the R&D deduction as a key and the income tax incentive as a door. The door won't open unless the key is turned far enough. The researchers found that income tax incentives only start to lower carbon intensity when a company's R&D spending crosses a specific line (a threshold value of 0.005).

If a company spends very little on research, the income tax reward is useless for cleaning up the environment. The company might just take the tax savings and put them into quick, easy projects that don't help the planet. But once the company crosses that threshold and starts spending significantly on research, the income tax reward suddenly becomes powerful. It's as if the company has finally built the engine (through R&D), and now the tax reward provides the fuel to make it run efficiently. The study suggests that for income tax incentives to work, companies must first be committed to the hard work of innovation.

On the flip side, the R&D deduction is a reliable workhorse. It lowers carbon intensity no matter what the income tax situation is. However, its power grows even stronger when income tax incentives are high. It's like a snowball rolling down a hill: the more snow (tax incentives) you add, the bigger and faster the snowball (carbon reduction) gets.

What This Means for the Future

The paper concludes that if governments want to clean up the industrial world, they shouldn't just throw money at everything. They need to be strategic. The R&D deduction is the most powerful tool, so it should be the main focus. Governments should prioritize making sure companies spend money on inventing green tech. Once that foundation is built, the income tax incentives can be turned on to supercharge the effort.

The researchers also point out that companies need to stop looking for quick wins. To truly lower their carbon scores, they need to invest in long-term green technology. The tax system is designed to reward this kind of thinking, but only if companies are willing to take the first step. By understanding these rules—especially the need for a certain level of research spending before income tax rewards kick in—policymakers can design better systems that help factories become cleaner, greener, and more efficient, all while keeping the economy moving forward.