Heating Homes With Switchgrass Pellets Could Save Northeasterners Billions And Cut Their Carbon Emissions

(Photo credit: Jock Gill)

According to a new cost-benefit analysis by the Agricultural Research Service (ARS), a switch from burning oil for heat to burning switchgrass biomass would cut down on both energy costs and carbon emissions for homes in the northeastern United States.

What’s especially significant is that study’s accounting of carbon emissions considered the entire life cycle of switchgrass, from crop planting, to growing, to harvesting and production. It still found switchgrass pellets yield a significant reduction in carbon dioxide equivalent (CO2e) emissions compared to both heating oil and natural gas, as well as a cost saving of just under $7 per gigajoule of heat compared to oil:

[T]he researchers calculated that using switchgrass pellets instead of petroleum fuel oil to generate one gigajoule of heat in residences would reduce greenhouse gas emissions by 146 pounds of CO2e. Using switchgrass pellets instead of natural gas to produce one gigajoule of heat in residences would reduce greenhouse gas emissions by 158 pounds of CO2e.

Substituting switchgrass pellets for fuel oil for home heating would also save money. Totaling all costs associated with installing an appropriate residential heating system and fuel consumption, Adler’s team concluded that each gigajoule of heat produced using switchgrass pellets would cost $21.36. Using fuel oil to produce the same amount of heat would cost $28.22. The savings would be less in a commercial facility, because capital costs for a commercial biomass boiler, storage, and fuel-handling equipment are five times greater than the costs for components that use fuel oil.

According to the team’s calculations, heating with switchgrass pellets would continue to be less expensive even if switchgrass production costs rose 200 percent and the price of fuel oil dropped 70 percent.

There some important caveats, to this as Clean Technica points out: First, the cost savings apply primarily to properties that are replacing old and outdated heating equipment, and thus will be investing in new equipment regardless. As noted above, the capital costs will significantly diminish savings for commercial rather than residential properties, though they won’t obliterate them. Second, the point applies to heating oil specifically — replacing gasoline with switchgrass biofuel would be difficult to justify currently, and replacing coal with switchgrass for electricity generation would significantly drive up energy costs. Third, the finding is specific to the Northeast region only.

But for the Northeast specifically, the ARS cites research indicating that by 2022 enough sustainably harvested biomass will be available to compensate for the entire regions demand for heating oil. That would save consumers something in the range of $2.3 to 3.9 billion in fuel costs per year, and cut the region’s carbon emissions by 5 percent. The finding also dovetails with President Obama’s “Better Buildings Initiative,” which aims, among other things, to take advantage of buildings and infrastructure with existing upgrade needs in order to improve energy efficiency and reduce energy bills. Finally, unlike other more widespread biofuels based on corn, for example, switchgrass has the economic and moral advantage of not doubling as a food source for humans.

So those caveats shouldn’t be interpreted to dismiss the importance of ARS’s analysis. The market is a huge and complex system, and how different people in different areas meet their energy needs are organic and myriad — how they move those needs from fossil fuels to renewable sources will be equally diverse. For the American Northeast, switchgrass for home heating looks like a compelling part of the mix. Every bite at the apple counts.

23 Responses to Heating Homes With Switchgrass Pellets Could Save Northeasterners Billions And Cut Their Carbon Emissions

  1. Sasparilla says:

    On one hand its nice to see this, but something to consider here of course is that this stuff has to be planted somewhere in large amounts. While this won’t be planted on currently cultivated farmland (hopefully) it will be planted on non cultivated land and if money can be made, on all of it possible over time – previously that “native” land was viewed as worthless and exploitable without consequences but as history has shown, that’s probably not really the case.

    As we farm every little possible bit that is exploitable, these little patches of wild areas left all over are valuable in many ways (safe havens for native species – plants, insects, animals – mostly) and I doubt that is being considered with these projection$.

    To turn our continent into nothing but farming, switchgrass mono environments and non exploitable areas (desert or swampland) probably would not be wise – it may be our destiny of course, but we should consider what we’re about to loose before we loose it and make an active choice. Not wake up 30 years from now and belatedly realize we’ve made a huge mistake (like we did with ethanol for example).

  2. First, a comment. The non-standard units quoted and lack of proportional comparisons make the numbers difficult to interpret, except that it appears from the ratio of costs per gigajoule of heat produced that the savings is likely within the error bar for this kind of projection.

    Another must-have caveat:

    Switchgrass does not compete directly in the market as a food crop. But it does compete for arable land, and given that the biodiversity crisis (largely due to land use impacts) is at least as acute as the climate crisis (though less well-understood), it is folly to propose climate “solutions” that would tend to increase cultivated or intensively managed land area.

    For this reason, among others, biofuels are a consistently dubious proposition.

  3. Joan Savage says:

    How much surface area (square meters) of switchgrass crop does it take per gigajoule of produced heat?

    Plant nutrients per gigajoule?

    The cost-benefit article is behind a paywall and nothing in the abstract mentions surface area or nutrients.

  4. Icarus62 says:

    Fossil fuels provide so much energy that they can pull themselves up by their own bootstraps – i.e. they can provide the energy to run society, and extract more fossil fuels, and process it, and bring it to where it is going to be used, and build and maintain and replace all the infrastructure used to produce power from them. Can any non-fossil fuels do that? In the case of switchgrass, can it produce enough energy to power ploughs, harvesters, trucks, processing plants, electricity generation plants, the mining and manufacturing processes for all that infrastructure and so on, and still produce enough power at the end of all that to run our civilisation? If not, then surely it’s a dead end? If not, we’d still need fossil fuels to power the trucks and mining machinery and factories to make trucks and mining machinery… and so on and so forth. This is the problem – there is so much embedded energy in fossil fuels that it’s very hard to find anything that is up to the job of replacing them. It’s all very well having a ‘renewable’ source of energy but if it’s only viable with the input of large amounts of fossil fuel, it’s ultimately futile. The energy itself may be inexhaustible and effectively infinitely renewable(solar energy) but the equipment we use to collect it is not.

    What have we got that is actually as good as, or better than, fossil fuels?

  5. DRT says:

    Perhaps switchgrass can be a reasonable bridge fuel to transition off of heating oil in the northeast, and I see that the ‘finding also dovetails with President Obama’s “Better Buildings Initiative”’, but can we make a technological leap and while doing energy efficiency upgrades, upgrade buildings to passive house standards. Yes, I know, this is not an easy thing. Instead of switching out the source of the fuel for heat, let’s get rid of the need for the fuel.

  6. Endofmore says:

    You cant burn grass to keep a civilisation warm
    Who’s nutty idea is that?
    Coal oil and gas is concentrated energy—grass isn’t
    ultimately we exist by extracting our life-energy from the land on which we live, every species of life is governed by that rule
    Not a pleasant thought, but we are meant to return the food we eat–and ultimately ourselves to that soil–just like everything else. A few thousand years ago, we decided to stop doing that, and appropriate the land for our own use.
    We even invented property ownership!
    Burning grass is in effect soil mining—we extract everything and set fire to it, ultimately the soil gets exhausted and won’t grow any more stuff.
    We are despoiling our environment, Nature is slow to deliver retribution to lawbreakers, but that is what she is doing now. We are being ejected from our earth home for being disruptive tenants and upsetting the peaceful existence of all the other tenants in the neighbourhood
    grassburning is a real sign of our desperation,,,,what next? Each other?

  7. catman306 says:

    7 gigajoules = 6.634 million Btus

  8. Rabid Doomsayer says:

    Insulation, insulation and insulation. Warmer in winter and cooler in summer. Works when the grid is down and when the switch grass pellet supplier is closed.

    Thermal mass and more thermal mass. Keep the cool through the hot and keep the warm through the cold.

    Efficiency in heaters; Longer hotter burn chambers like a rocket stove to burn all of the available fuel and then longer heat extraction and storage like a thermal mass rocket stove. Our existing systems are so very inefficient that an efficient system seems like magic.

    We could build houses that have minimal heating and cooling requirements even in the most extreme of climates. We could do so much even if we just avoided the foolish construction choices.

  9. Mulga Mumblebrain says:

    Thirty years ago we will be in the midst of a waking nightmare.

  10. catman306 says:

    Your argument ignores the negative effects on our environment that mining and burning fossil fuels entails.

    Robbing banks for a living works fine until you get caught. Climate disruption and environmental degradation are just now catching up with us. There is a heavy price to pay for our crime against nature.

  11. Merrelyn Emery says:

    You don’t have to burn anything. We have that lovely big generator just 93m miles away, ME

  12. David F Collins says:

    How about miscanthus giganteus? I have read of work by Dr Emily Heaton at the University of Illinois (Champaign) and Iowa State University (Ames) indicating significant potential as a biofuel.

  13. And how many BTUs does the average house use? Hate to be lazy, but I figure it’s the job of the authors to translate this into something that’s immediately useful to the audience. Will this save New Englanders $30 a month? $00.02 cents a month? It would be helpful to know, especially if you’re a New Englander who is thinking about investing in a switchgrass stove.

  14. Joan Savage says:

    I agree with you about biodiversity versus monoculture.

    Neither the write up nor abstract reveal how that would be addressed.

    The proponents of switchgrass are probably astonished at the critiques here. Switchgrass is a native plant, a perennial with deep roots that make it drought tolerant. It is a common part of diverse prairie biota, and it is part of wildlife habitat.

    If the switchgrass is grown in a permaculture, as part of a diverse habitat, it might survive our critiques. If it means marginal crop land is returned to grassland with greater drought tolerance and greater erosion resistance, it could be a good thing.

    I don’t need to burn it to like the other benefits of the plant.

    Presenting it solely as a comparative CO2 reduction didn’t satisfy, obviously.

  15. The energy returned for energy invested for fossil fuels has dropped from something like 30:1 at the beginning of the fossil-fuel age to 1.4:1 today — and it’s still dropping. It’s negative if you count the “externality” of cleaning up the fossil-fuel residue as part of the equation.

    But just from the standpoint of LCOE, fossil fuels are getting more and more expensive, while renewables are getting cheaper and cheaper. Remove the subsidies for fossil fuels, including the hidden subsidies like the railroad tracks the country maintains that the coal companies use to ship their toxic product, and renewables are already positioned to win on a cost basis alone.

  16. Right on. There are some places where that might not work — in which case we would be better to use switch grass or wood pellets than oil. But for the most part, even New England can be heated with a combination of solar and body heat, if the homes are properly insulated.

  17. Paul Klinkman says:

    Some people are selling wood pellet furnaces. They work like coal furnaces except their feedstock is sawdust wood pellets. These switchgrass pellets should work well in them.

    The real purpose of stored switchgrass and stored biofuels is to take up the slack on those odd days when solar fails, when wind power fails, and then when a short-term backup such as pumped hydro runs out of power. Stored biofuels have a shelf life of forever and they don’t take up that much room.

    Switchgrass grows best on cropland that we want for food. That’s a big problem.

    Switchgrass is better than corn. You should know that people are starting to sell corn-burning furnaces. This sounds obscene in a world of massive hunger.

    In my opinion, algae is going to eat switchgrass for breakfast some day. A one-celled animal is inherently ready to photosynthesize sunlight into oil with little energy waste for things like roots or stems.

    My second choice would be to irrigate low-lying deserts such as the area around the Salton sink (now the Salton Sea) in California near Mexico, with salt water. Mangrove trees can grow in salt water. There must be shoreline reeds, algae and other crops that can survive ocean water.

    Much of the Sahara desert could be irrigated with salt water. Use wind power to pump the water up from sea level. An artificial marsh in the desert naturally raises the surrounding desert’s humidity, which causes fog-loving plants to thrive nearby.

  18. Merrelyn Emery says:

    And don’t foget passive solar. I once had a spec built house that was badly designed and sited but with a few minor renovations became solar positive and the bills went down immediately, ME

  19. Merrelyn Emery says:

    Great ideas Paul, ME

  20. Icarus says:


  21. Icarus62 says:

    “Your argument ignores the negative effects on our environment that mining and burning fossil fuels entails.”

    No no, I entirely accept those things. My point is that we won’t be able to do away with those negative effects unless and until we find something that can completely replace fossil fuels. Can we build a new energy system and then one day close the last coal mine, shut down the last oil-fired power station, dismantle the last natural gas drilling rig? Or would we find that actually we can’t run all the mining and manufacturing and transport and other infrastructure on ‘renewables’ alone?

    I *want* to be able to tell my politicians to pull their fingers out and get moving on replacing fossil fuels, but at the moment I don’t know of any alternative that has sufficient versatility and embodied energy to let us do that. At the moment, all ‘renewables’ are just extensions of our fossil fuel energy system and cannot stand on their own. I don’t want to be advocating for something that’s a dead end and ultimately another waste of resources.

  22. Mulga Mumblebrain says:

    It’s the ‘monocultures of the mind’, as Vandana Shiva observed, that are doing humanity in.

  23. Mulga Mumblebrain says:

    If there is a buck in it-just try stopping the ‘entrepreneurs’.