In today’s Finshots, we talk about KGF making a comeback. No, not the movie, but the actual gold fields that are just a couple of hours away from Bengaluru.
What if we tell you that a former gold mine could be a massive source of renewable energy? Sounds insane, right?
Well, last week The Hindu published quite an unusual story. It said that an Australian firm called Green Gravity has a wild idea to revive the defunct Kolar Gold Fields of Karnataka.
For over 12o years, KGF was the pride of India. It was the world’s second-deepest gold mine and produced 95% of India’s gold at one point. But it fell into disarray in the 2000s. The costs of mining were too exorbitant and it wasn’t generating enough money. KGF was abandoned.
But a radical idea might just be able to turn its fortune around. KGF might just get a new lease of life as a ‘battery storage’ facility. How, you ask?
Let’s begin with the concept of energy. Remember the physics class in school when the teacher said — “energy can neither be created nor destroyed, only converted from one form of energy to another”?
Well, it simply meant that everything around you has some form of energy. Always.
For instance, just look at those books on the top of your shelf. They might seem like inanimate objects. But they actually have something called gravitational potential energy. It’s the energy stored thanks to its elevated position. Now give them a little nudge. Tip them onto the floor. Suddenly, this energy is converted into kinetic energy. This is the kind of energy that can be used to generate electricity.
Now think about the KGF mines which in some cases are 3 km deep. Imagine that you take a massive cement block that weighs 40 tonnes. You use a motorized pulley and lift it to the top. And you don’t need traditional electricity to do the pulling. You can rely on solar energy or wind energy to work the pulley. And once you stack a bunch of blocks at the top, they’re all bursting with gravitational potential energy.
Then, when you need power, say when the sun has turned in for the night, you drop the cement blocks. We’re not saying that it’ll be dropped for the entire 3 km in freefall. But, a calculated drop to a certain extent. When it falls, the latent gravitational energy is converted into kinetic energy. This can then be used to power turbines and generators.
And voila, you have electricity!
All you need is an abandoned old mine. And a bunch of cement blocks.
The deeper and broader the mine, the more power you can extract. And the larger the mine, the more the energy storage capacity.
But why could this be quite the game changer, you ask?
Well, one of the biggest hurdles we have in the shift towards renewable energy is figuring out how to store it all. Take solar energy. It’s the most abundant energy source out there. On average 173,000 terrawatts of solar energy hits the earth continuously. And that’s 10,000 times more than what the world’s current energy needs.
But the sun doesn’t shine bright every day. And well, it sets at night too like clockwork. During these times, we can’t just postpone our energy needs, no?
We need to find a way to store it in batteries for future use. That’s the only way we can beat nature’s vagaries and use it day and night. In rain or sun.
But deploying large-scale battery solutions for solar is still quite cost prohibitive. So it can’t really be used to power entire cities easily. So that’s out of the question for now.
Then we have the ever-popular lithium-ion (Li-ion) batteries. The kind that runs electric vehicles. But on a large scale, they have their own issues. For starters, there’s the cost. It’s still not cheap and can cost around $370 per megawatt hour (MWh) over its lifetime. For perspective, 1 mWh of power can run two refrigerators for a year. Also, these batteries aren’t exactly known for their long life. Frequently charging and discharging them could keep their life as short as 3–5 years. Just think about your mobile phone battery and how quickly it begins to underperform. Besides, a single Li-ion battery may not be able to store beyond 4 hours of charge at a time. And it also uses a lot of elements like lithium, nickel, and copper which will deplete over time.
And that’s where these gravity batteries have a huge advantage.
Just think about it — they’re just large gravel blocks made up of cement. That means it’s not high maintenance and the whole set-up could probably last up to 50 years. And when researchers calculated the costs, they came up with a very low figure. They believe it’ll cost just $170 for 1 MWh of electricity. That’s less than half of the lithium-ion alternative.
Also, storing big blocks isn’t a problem since we’re just using abandoned mines. Just look at India which has at least 250 unused coal mines that could do with a new lease of life. And across the world, there are over a million of them!
But wait…it can’t all be sunshine and butterflies, no?
Well, for starters these are mechanical contraptions that could break easily and the costs may prove prohibitive. There’s also the fact that we have very little evidence to show that gravity batteries can scale and offer energy sustainably. It may work well for very specific applications. But as a broad solution to our energy problem? That is a tall ask.
So yeah, there’s never going to be a perfect solution. But this wacky idea does seem promising. And if the Indian government okays Green Gravity’s idea, not only would it be a step towards large-scale renewable power use, but it could also have the advantage of reviving KGF and spur the employment of at least part of the 2.5 lakh people who reside there.
Until next time…
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PS: India’s NTPC signed an MoU in 2022 with a company called Energy Vault Holdings to create such gravity-based renewable energy. So it’s not so crazy, is it?
Ditto Insights: Why Millennials should buy a term plan
According to a survey, only 17% of Indian millennials (25–35 yrs) have bought term insurance. The actual numbers are likely even lower.
And the more worrying fact is that 55% hadn’t even heard of term insurance!
So why is this happening?
One common misconception is the dependent conundrum. Most millennials we spoke to want to buy a term policy because they want to cover their spouse and kids. And this makes perfect sense. After all, in your absence you want your term policy to pay out a large sum of money to cover your family’s needs for the future. But these very same people don’t think of their parents as dependents even though they support them extensively. I remember the moment it hit me. I routinely send money back home, but I had never considered my parents as my dependents. And when a colleague spoke about his experience, I immediately put two and two together. They were dependent on my income and my absence would most certainly affect them financially. So a term plan was a no-brainer for me.
There’s another reason why millennials should probably consider looking at a term plan — Debt. Most people we spoke to have home loans, education loans and other personal loans with a considerable interest burden. In their absence, this burden would shift to their dependents. It’s not something most people think of, but it happens all the time.
Finally, you actually get a pretty good bargain on term insurance prices when you’re younger. The idea is to pay a nominal sum every year (something that won’t burn your pocket) to protect your dependents in the event of your untimely demise. And this fee is lowest when you’re young.
So if you’re a millennial and you’re reading this, maybe you should reconsider buying a term plan. And don’t forget to talk to us at Ditto while you’re at it. We only have a limited number of slots everyday, so make sure you book your appointment at the earliest:
1. Just head to our website by clicking on the link here
2. Click on “Book a FREE call”
3. Select Term Insurance
4. Choose the date & time as per your convenience and RELAX!