Renewable resources

Topic: Environment and Sustainable Development · NCERT: Class 10, Ch 1 "Development"; Class 11, Ch 7 "Environment and Sustainable Development"

Meaning

Renewable resources are resources whose supply keeps renewing itself through nature, such as trees in forests, fish in the ocean and groundwater. They can be used without running out, but only if we take them no faster than they regrow.

This matters because "renewable" does not mean "unlimited". If people use a renewable resource faster than it regrows, the stock falls, just as a non-renewable stock does. The safe rule is:

Resource extraction ≤ rate of regeneration

Explanation

How a renewable resource works

• Supplying resources is the first function of the environment. It gives us both renewable and non-renewable resources, and these feed production and consumption.
• A renewable resource has two parts:
• Stock: how much exists right now, such as the number of trees in a forest.

• Regeneration rate: how much nature adds back each year, such as new trees growing or rain refilling groundwater.

• Regeneration means nature rebuilding the stock by itself, through growth, breeding or rainfall.

• Renewable resources can be:
• biotic (living parts of the environment), such as forests and fisheries
• abiotic (non-living parts of the environment), such as groundwater

The Class 10 trap: renewable ≠ unlimited

• Renewable resources can also be overused.
• Groundwater is renewable.
• If we pump out more than rain puts back, the water table falls.

• This is overuse, even though the resource is "renewable".

• So the difference between renewable and non-renewable resources is not about what happens when you use them carelessly. Both can run down.

• The difference is that a renewable stock can recover if extraction is kept below regeneration. A non-renewable stock cannot recover.

Carrying capacity: the safe limit

• Carrying capacity means the limit within which the environment can keep doing its functions. Two conditions must both hold: 1. Resource extraction ≤ rate of regeneration. This condition is about renewable resources. 2. Waste generated ≤ assimilating capacity (how much waste the environment can absorb and break down).

• Worked example: a forest regrows 100 trees a year.

• If we cut 80 trees a year, extraction (80) is less than regeneration (100). The stock stays healthy.
• If we cut 120 trees a year, extraction (120) is more than regeneration (100). The stock falls by 20 trees every year.
• In the second case, the forest is being used beyond its carrying capacity. A renewable resource is now being run down like a non-renewable one.

What makes the stock rise or fall

• Stock falls when:
• rising population in developing countries means more people need resources
• affluent consumption and production in developed countries means each person uses far more resources

• pollution or deforestation damages the resource's ability to regrow. A polluted river, for example, can no longer supply clean water.

• Stock holds or rises when extraction is kept below regeneration. This is the idea of "sustainable yield" (the amount you can take each year without shrinking the stock). The idea comes from forestry and fisheries. The Brundtland Report widened it into the general idea of sustainable development [4].

• Supply-demand reversal:
• Before industrialisation, demand for environmental resources was less than supply, and extraction was slower than regeneration. Water and forests were, in effect, "free goods" (goods so plentiful that nobody needs to pay for them).
• After the population explosion and the Industrial Revolution, demand went beyond the rate of regeneration.
• So even renewable resources became scarce economic goods, with a price and an opportunity cost (the value of the next-best thing given up).

In India

• Groundwater is the textbook Indian example.
• It is renewable because rain recharges it.

• Where pumping is more than recharge, the water table falls. This is the Class 10 overuse trap.

• Water stress (NITI Aayog, Composite Water Management Index, 2018):

• About 600 million (60 crore) Indians face high to extreme water stress [7].
• Nearly 70% of water is contaminated, and India ranks 120th out of 122 countries on the water quality index [7].

• NCERT also says about 70% of India's water is polluted. This raises respiratory and water-borne diseases.

• Why pollution matters for a renewable resource:

• A river renews its water, but a polluted river cannot supply usable water.

• Degradation (a fall in quality) therefore cuts the useful supply, even when the quantity is still there.

• Central Pollution Control Board (CPCB):

• It was set up in 1974 under the Water (Prevention and Control of Pollution) Act, 1974 [2][3].
• Its main function is to promote cleanliness of streams and wells in different areas of the States [2][3].

• It protects the environment's waste-assimilation function, which keeps renewable water fit for use.

• Forests:

• Forests (biotic) hold soil and recharge groundwater (abiotic).
• So losing forests harms more than one renewable resource at the same time.

Don't confuse with

• Non-renewable resources: they run out as we extract them, and their stock is fixed, for example coal, crude oil and natural gas. New discoveries add to the stock, but it will still run out. A renewable resource can recover if extraction stays below regeneration.
• Unlimited / inexhaustible resource: "renewable" does not mean unlimited. Groundwater, fish and forests can all be overused (Class 10).
• Resource depletion vs environmental degradation: depletion is about the quantity of a resource, such as cutting trees faster than they regrow. Degradation is about the quality of the environment, through pollution, deforestation and soil erosion.
• Carrying capacity vs absorptive capacity: carrying capacity covers both extraction ≤ regeneration and waste ≤ assimilating capacity. Absorptive capacity is only the ability to absorb degradation, such as a river breaking down a limited amount of sewage.

Prelims Hooks

• Renewable resources: supply regenerates, e.g. trees in forests and fish in the ocean. Non-renewable resources: fixed stock, e.g. fossil fuels (Class 10).
• Trap: groundwater is a renewable resource but can still be overused when pumping is more than rainfall recharge (Class 10).
• Carrying capacity needs two conditions: extraction ≤ regeneration and waste ≤ assimilating capacity.
• "Supplies resources (renewable and non-renewable)" is the first of the environment's four functions. The environmental crisis is the failure of the third function, sustaining life.
• The Brundtland Report, "Our Common Future" (1987), took "sustainable yield" from forestry and fisheries and widened it into sustainable development [4].
• Dublin Statement (January 1992): its 4th principle recognises water as an economic good [5].

Mains Points

• Renewable resources can be mismanaged too
• India's groundwater crisis shows that a renewable resource can be run down like a non-renewable one.
• About 600 million Indians face high to extreme water stress (CWMI, 2018) [7].

• Policy should therefore cap extraction at the recharge rate and invest in recharge. Being "renewable" is not a reason to relax.

• Pricing renewable resources: efficiency vs equity

• The supply-demand reversal turned free goods such as water into scarce economic goods. This supports pricing, as in the Dublin principle [5].

• But treating water as a commodity has legal, institutional and regulatory effects, and it must be balanced against the right to water and fairness to the poor. This is why the Dublin debate was long and contentious [6].

• Energy security through renewables

• India imports most of its oil, and world crude reserves would last only about 47 years at the 2017 rate of production.
• Under the Hotelling rule, the net price of a non-renewable resource rises at the rate of interest, so scarcity keeps pushing prices up.
• This supports shifting to renewables, improving efficiency and building strategic reserves. It is a useful GS-III argument that environmental protection is a growth investment, not a cost on growth.

Related concepts

• Environment
• Biotic and abiotic components
• Functions of the environment
• Non-renewable resources
• Reserves-to-production life
• Hotelling rule
• Carrying capacity
• Absorptive capacity
• Environmental crisis
• Supply-demand reversal of environmental resources

Read more

• The environment, its functions and the supply-demand reversal