Horsepower to poop power: Horse manure better at generating electricity, heat

HorsePower may have a new meaning soon after researchers have found a new way to generate electricity without using fossil fuels. It turns out that horses that are so quick and efficient in transporting weights are also good at digesting food quickly and generating lots of manure that can be used to generate electricity.

With countries setting targets to achieve net-zero emissions in the coming few decades, there is a rush to switch away from coal and gas and use more environmentally friendly sources of energy. While solar and wind power installations are happening quickly, there is also the need to tide over their intermittent nature.

Using animal waste instead can be a welcome step for those who shrug at nuclear energy. Traditional methods include drying animal manure and using it as fuel in fire. However, with advances in technology, it is now possible to generate electricity without burning animal poop.

Electricity from animal poop

Most conventional methods of electricity generation involve using fuel to turn water into steam, which is then used to turn turbines and generate electricity. While manure could also be used as a direct fuel, scientists have turned to a much more efficient means of doing so.

Anaerobic digestion is a process in which microorganisms decay organic matter in the absence of oxygen. Large containers called digesters can replicate this process in more controlled conditions. Certain microorganisms convert the manure into methane gas, which can then be used as fuel in a power plant.

An alternate method involves heating wet manure directly in the presence of air and generating steam that can push turbine blades.

With livestock farming a major contributor to greenhouse gases, these approaches offer another way to add value to the activity while also moving away from fossil fuels. Cattle farms can repurpose their manure, but horse farms have an advantage here.

Why horses are better

Horses digest their food much faster than cattle; the food-to-waste timeline is at most 72 hours. On average, a horse produces 60 pounds of waste daily, much more than a dairy cow’s 18 gallons a day.

Moreover, horse manure is drier than cow manure and rich in nutrients since horse feed is of higher quality than the grass cows graze on. This makes horse manure much superior and has the potential for higher energy production when used in digesters.

Making electricity from horse manure also solves another problem for businesses that use horses – disposing of horse waste. The challenge, however, is that an energy-generating center needs to be located near these facilities.

Interestingly, this has been attempted and demonstrated before. In 2019, a Finnish company, Fortum , used wood by-products to make horse bedding, participating in the Helsinki International Horse Show. The horse manure and bedding were then used to generate heat for a nearby power plant, and 140 MWh of energy was generated from the unit.

This energy was used to provide electricity for conducting the international show. Still, on any other day, it could have provided the energy needs of 6,500 houses. With horse farms located far from the city, the approach can also be used to meet the energy demands of the local area sustainably.