Can Yard Grass Be Turned Into Burnable Logs or Grill Pellets?

I’ve been experimenting with an idea and wanted some honest feedback from people who know more about biomass, grilling, or off-grid living.
The idea is straightforward: take regular grass clippings from your yard, dry them, compress them, and turn them into burnable logs or grill pellets.
Here’s what I’ve figured out so far:

Burn characteristics:


Dried, compressed grass burns in a neutral way, similar to plain charcoal. If you just want clean heat with no added flavor, it seems to work fine on its own.

Grilling flavor:


The grass itself doesn’t add flavor. But you can mix in real wood powders (apple, hickory, pecan, cherry, etc.) during compression if you want smoke flavor. That would let you make either neutral pellets or flavored ones.

Fertilizer safety:

From everything I’ve researched, once grass is fully dried and burned, fertilizer residues combust cleanly. The grass is just the heat source.

Energy comparison:


To match around 10 kg of charcoal, you’d need about 17–18 kg of dried grass pellets or logs. If you’re starting with fresh grass, that comes out to roughly 60–90 kg depending on moisture.

Why even consider this:

It would turn yard waste into free fuel, reduce the need to buy charcoal or pellets, and create an eco-friendly, zero-waste option. You could use it for grilling, heating, or off-grid setups, and add wood flavor if you want it.
I attached a rough blueprint of the concept for anyone who wants to look.
I’d really like honest feedback on this. Does it seem useful or not worth the trouble? What problems do you see with it? Anything I might be overlooking?

There appears to be an assumption that all grass produces the same BTU.   Trees  produce different BTU depending upon species. I suspect grass does as well.  Otherwise, what you present is interesting.

It is feasible, probably done in some areas of the world already, at least for ag waste. But if you do the energy equation, you might find it is more expensive than the return (you would be better off in dollars and carbon emissions to burn the diesel directly for heat).

Instead of purchasing some expensive equipment why not make something like this on a smaller scale, the size of a wood stove, maybe the size of those logs:

https://permies.com/t/287661/tech/Building-Manual-Baler

It's a great idea, however my suspicion is that the amount of energy needed to dry and pelletise the grass might make it far from free fuel, unfortunately. If you start with 60-90 kg of grass to end up with 17-18 kg of finished pellets, that's a lot of water to evaporate off. If there was some way to utilise solar drying kiln technology for that, or somehow air dry the grass like hay without it fermenting it, the idea could be feasible. I checked a few different sources to find out the likely heat required, and it looks like doing it all inside a machine like your illustration would require approximately 35 kW of energy per 50kg of water removed.

I'd also be concerned about chemicals used on lawns being in the grass -- various herbicides and pesticides they many conventionally gardening homeowners use.

Jane Mulberry wrote:It's a great idea, however my suspicion is that the amount of energy needed to dry and pelletise the grass might make it far from free fuel, unfortunately. If you start with 60-90 kg of grass to end up with 17-18 kg of finished pellets, that's a lot of water to evaporate off. If there was some way to utilise solar drying kiln technology for that, or somehow air dry the grass like hay without it fermenting it, the idea could be feasible. I checked a few different sources to find out the likely heat required, and it looks like doing it all inside a machine like your illustration would require approximately 35 kW of energy per 50kg of water removed.

I'd also be concerned about chemicals used on lawns being in the grass -- various herbicides and pesticides they many conventionally gardening homeowners use.

The beauty of this system is that part of the invention is the mower dries some of the grass without letting the exhaust touch the grass. Of course the drying can not keep up with the quantity of grass in the machine which the rest will have to be put in the collection bin that uses solar power to dry and a small amount of electricity. All fertilized grass losses all possible contaminants through the burning process so there is no chance of any herbicides or pesticides affecting the process this is already been stablished in my study. And yes, if the amount of energy needed is more than we produce it will not be justified to have this process. Any time you can use a bi product that you have to get rid of it is always going to be a plus.