Heating Homes With Human Waste Is Saving Lives And Tigers In Nepal

One man’s waste can quite literally be another’s gold. Biogas is a clean, odorless, and life-changing source of energy that saves women from spending all day looking for firewood, and thus saves the forests that are home to tigers.


Dirt gets a bad rap. I’m sitting on a
dirt floor in Badreni, Nepal, in a home built largely of dirt (waddle
and daub) and there’s nothing dirty at all about this place. I’m
a guest in a biogas home–one of 7,500 the WWF has helped build to date and
one of 40,000 that will dot this Nepalese landscape five years from

small but powerful blue flame whispers in the corner and brings light to the faces of my host family. That flame lights and
heats the home; it also warms the Chiya tea we’re all anxious to drink.

The biogas home is about as low
on the low-tech totem pole you can go because it all begins with, well… let’s just say that one man’s waste is quite literally another’s gold
in this equation. Cow dung, human excrement and a bit of water make up
the slurry that ferments in a simple cement-lined pit. Some elbow
grease to stir a crank, a heavy dose of microbial action and–voila!–a clean, odorless, and life-changing gas.


I say that this is life-changing because women once confined to a smoke-filled kitchen area for
much of the day no longer face an almost certain future of respiratory
illness. It’s life-changing because those same women no longer have to spend two to three hours of every day
searching for sticks or hacking trees in a forest with some very cool
but rather unfriendly neighbors (think snakes, rhinos, elephants, and
the highest density of tigers in the world). That
time saved can be spent on everything from enjoying the Himalayan
backdrop in the company of family to going to school. And the spent slurry can be used as potent and easy-to-work fertilizer that
dramatically bumps crop productivity and food security.

That little blue flame has become a symbol of hope and a powerful tool for overcoming poverty in this landscape.

in what’s called the Terai-Arc of Nepal, a narrow band of forests and
grasslands nestled in the foothills of the mighty Himalayas. “Pristine” or
“primeval” are words that don’t work here. Humanity has kneaded this
place into a patchwork of villages and secondary forests. Eleven
protected areas–like Chitwan and Bardia–form something of a conservation core. WWF, the local and national
government, and the communities themselves have been working to reforest
and stitch this place together in a way that benefits both people and
animals. Again, enter the blue flame.


typical non-biogas household will char about five and a half pounds of
fuel wood a day to light and heat their space and to cook meals. Any woody debris from the immediate surroundings quickly gets picked clean. So there is a progressively more distant, more dangerous,
and more destructive daily exodus into the forest to find fuel.

homes are great for Nepalese families, but they’re also integral to
forest reforestation and conservation, the survival of endangered fauna
like tigers, and even to the stability of the climate. The
demand for these stoves has spiked recently because the benefits are so
tangible and immediate.

Part of the success of the stoves as a whole
can be attributed to the cost-sharing, micro-lending approach we’ve
used. One unit costs $548 (about 40,000 Nepalese Rupees). WWF has
agreed to subsidize 25% of that cost ($137) through Nepal’s Alternative
Energy Promotion Center. We also subsidize the $27 per unit toilet cost (I
never imagined using that phrase in pursuit of saving tigers). And we
also spend approximately $34 per unit to monitor the use and functioning of
the equipment and to support maintenance of the plant.


leaves families with a $384 gap–and that’s where things get
interesting. Interest rates charged by the local banks are too high and
require collateral. So we created microfinance institutions at the
community level and established a revolving fund for the project that
provides a soft loan at an interest rate of 8% (almost one-third of the
general bank rates) with a duration of two years. The repayment rate is

revolving fund was capitalized with donations from WWF supporters the
world over and, importantly, with the sale of Gold Standard credits from
the voluntary carbon market. The 7,500 stoves save 617 acres of forest
annually; that means 33,000 tons of fuel wood isn’t being torched. Each stove
eliminates four metric tons of CO2 equivalents annually, and those carbon
savings are traded by a Swiss-based organization, My Climate.

At a price
of $18.50 per ton of CO2 equivalent, we can reach a break-even point on the
biogas project in the seventh year. Since the average life of a biogas
plant is 20 years, revenue after the seventh year will help us construct
more biogas plants in Nepal, making this initiative sustainable. The
whole complicated economic and ecological chain is a
model for ensuring that local people benefit from emerging programs like
Reduced Emissions from Deforestation and Forest Degradation (REDD).


Maya Tamang, the woman who has taken me under her protective wing and
who has schooled me with regards to the intricacies of biogas, refills
my cup with more tea. After sharing stories,
translated with tremendous patience by her brilliant, multi-lingual
son, Jari closes the valve and the blue flame expires, leaving us
wrapped in darkness and the fragrance of tea.

[Image: Carter Roberts]

As President and CEO of WWFUS,
Carter Roberts leads World Wildlife Fund’s work to save endangered
species and their habitats through innovative programs with governments,
businesses and local communities throughout the world. WWF, famous for
its panda logo, is the world largest conservation network, with over 6
million members and programs across 100 countries.


About the author

What do tigers, a can of Coke and valuing the rainforest have in common? They can all help save the world. "Stay with me for a minute here," says Carter Roberts, laughing. Conservation, ultimately, is all about achieving harmony between people and nature