Rice is arguably one of the most widely consumed starches.

Yet because of this, it leaves behind millions of tonnes of waste also known as rice husks.

Now these husks are good for running boilers or even making basic fertlizers for use in the farm.

But what if we were to think of more valuable use for this trash.

Mind you, this is no new arena since some innovators seem to be making some headway.

So let’s consider four areas: energy, water, food and packaging.

ENERGY

There’s no doubt that there’s an increased need for renewable energy today.

An when considering renewable, solar just doesn’t seem to be left behind.

Buy what does solar energy have to do with rice husks?

Well, rice husks are unique in one striking way – they are rich in silica.

Now silica is not just your ordinary waste material, it could be used to make silicon – the stuff used to build conventional solar panels.

Now this process might not be as straightforward but it still is possible and a few rugged, risk taking innovators have tried and tested these waters to some degree of success.

But solar panels isn’t the only front rice husks could conquer on the energy front.

Silicon is also considered a valuable replacement for lithium in future lithium ion batteries.

Reason being that it processes a higher energy storage capacity.

What this means is that a gram of silicon could deliver more energy than a gram of lithium.

So far, this innovation has not yet found a footing in the market because of the rapid deterioration of silicon during the battery charging and discharging process.

So that’s a subject of deeper research.

But why bother with batteries?

Well, one of the richest chaps in the world, Elon Musk was thrown into the limelight by the success of his electric car company- Tesla.

Now Tesla vehicles use lithium ion batteries – but of course they’re researching on other viable options for the future.

This is not to mention an increase in hybrid vehicles we see on our streets partially powered by lithium batteries.

Rice husks could also be employed in other energy related applications such as manufacture of briquettes and bioethanol – which is of greater interest given it’s cleaner energy.

Beyond these snippets on the energy front, rice husks are rich in applications to do with water treatment.

WATER

Rice husk ash has been tried and tested in water treatment with varying efficiencies

In rice growing areas like in South East Asia, many households innovate filters using rice husk ash to remove dissolved pollutants which can’t be filtered off in a different way.

So whether we are talking of removal of toxic heavy metals, fluoride, water hardness, pesticides etc. rice husk ash is useful to some degree.

But even better, if the rice husk is converted to carbon – by burning in absence of oxygen – its use as a water filter improves a hundredfold (figuratively).

Rice husks could be converted into biochar or activated carbons this way making them very useful.

So probably instead of buying water for drinking, one could improvise a rice husk ash filter to test its viability in water softening.

And if it works, one could convert it into a product for the market.

And this technology has been tried and tested using carbons derived from other agrowastes such as coconuts.

FOOD

Rice husks are rich in silica.

Now silica is useful in the soil because it forms a significant proportion of it.

Rice husks have therefore been used successfully as soil amendments capable of loosening clay soils while offering good water retention capacity at the same time

So combining rice husks with compost or other growing mediums such as coco coir helps in building fertile organic soils.

But rice husks also contains cellulose – a natural and easy-to-extract commodity.

Naturally derived cellulose (biocellulose) could he useful in the future as a matrix for manufacture of fertilizers – a solid material that could hold agricultural nutrients for crops.

Now this looks utopian but there are slow release fertilizers in Western nations using artificial matrixes which could be substituted by cellulose from husks.

Slow release fertilisers – unlike conventional fertilizers – release nutrients slowly over a longer period of time reducing wastage.

PACKAGING

Being lightweight waste, rice husks could be useful in manufacture of packaging.

Already there are startups blending waste plastic with rice husks to mold them into cutlery and some kitchen appliances.

Better still, rice husks could be pulverised then mixed together with a natural food grade adhesive like starch and used to make Lunch boxes, spoons etc for sale.

The same is being done using wastes from pineapples and sugarcane.

Probably it’s also time to innovate fully on the rice husk front.

IN CONCLUSION

As long as we continue to exist, we shall always generate agricultural wastes.

The problem is that this trash contributes to solid waste pollution.

However we could innovate useful products from these waste materials thereby reducing their negative effects on the environment.

And this is where rice husks comes to play.

Mind you, these are just ideas to provoke anyone.

Think outside the box – or eliminate the box altogether. 

Think of creative ways of using rice husks – and any other agrowaste – and you just might make a living out of it.