Many homes use hot water boilers as an efficient source of heat during the winter with a separate water heater tank. Others have a combination boiler that run all year to make both. Either option is good and reliable in its own way. If you’re replacing one of these systems, you may want to think slightly outside the box for a different approach.
What I’m referring to is a technology called MCHP (Micro-Combined Heat and Power). This type of equipment is a singular home utility appliance functioning as a boiler, water heater and electrical generator all in one.
Types of Equipment
More than a few manufacturers exist, each offering a nice piece of equipment. Yet, in the grand scheme of things, I feel there should be more. Some names that come to mind are Yanmar, EcoPower, and Qnergy. Additionally, many brands are available for use globally, but getting others installed within the States is another story.
Safety regulations in the US, such as Underwriters Laboratories (UL Listings), make it very expensive for new technologies to emerge. The importance of these regulations hardly goes unnoticed, but naysayers are quick to point out how they can stifle innovation.
Of the units available in the US, common sizes generate 3, 5 and 10 kilowatts of electricity. If you put that into perspective, a 3 kW unit would create enough power to run most lights in a small house plus the refrigerator. 3 kW units may generate up to 30,000 BTUH of heat – about the size of a small water heater.
10 kW MCHP units can produce up to 100,000 BTUH of heat. This could heat a typical two-story, three-bedroom, well-insulated house, while generating enough electricity to handle the lights, a refrigerator, and a pool pump.
MCHP can also heat pool water eliminating the need for a heater. This is a great application for hotels with indoor swimming pools.
Example Project Cost
Let’s do a case study to break down the MCHP cost using round numbers (not reflecting actual quoted prices).
Take a 2500 square foot home in Suburban Philadelphia with $3000 in electric bills and $2000 in gas annually. The homeowners previously invested in air sealing (to reduce drafts), and insulation upgrades. On a scale of 1-10 for efficiency, it gets a 7.5.
Replacing a 100,000 BTUH combination boiler and installing a 10 kW generator may cost in the neighborhood of $15,000 – give or take. If a 10 kW MCHP unit were selected, the total cost for the system could be double or slightly more.
What makes MCHP worth the investment? The payback, and it comes in the form of electrical generation. Some utility companies may offer of a reduced natural gas rate for MCHP.
In the example, the MCHP unit is projected to pay back about 35% of the annual cost of utility bills. That’s $1,700 savings per year (subtracting additional gas usage for MCHP). This roughly calculates into a 15-20 year payback cycle without subsidies or other financial justifications.
Importance of MCHP
Predictions for the next decade show an increase in electric vehicles usage. This means more dependency on the electrical grid. Artificial Intelligence is a major topic of conversation over this period, specifically for autonomous electric vehicles. If this becomes reality, the US will require exponentially more electric than we currently use today.
Decentralizing our grid would help create a smoother transition for a country in need of more electricity. This happens when you forgo building large centralized plants and rely on power from MicroGrids. These smaller systems distribute power generated on a house to house basis including a combination of sources like MCHP, solar, wind, battery storage, etc.
Comparing MCHP to Solar
The cost comparison for a solar project versus MCHP is in the same ballpark. Paybacks may vary. My research shows MCHP to be very competitive against solar in areas with more heating months and gray skies. Cough…Philadelphia.
Even without subsidies, MCHP averages a near 15-year payback where solar is around 20-years.
Demand for MCHP
A spike in demand hit for Green Tech back in 2012 resulting from the superstorms, which nearly devastated the Northeastern US. Areas hit hardest by those storms still have reasonable programs in place for tech, like MCHP, to make good practical and financial sense.
As for the 2500 square foot house in Suburban Philadelphia (formerly mentioned in our Example Project) – consider the facts: The owners are 30 something, starting out in their respective careers, have two small children and modest savings. An extra $25k for Green Tech with a 15-year payback isn’t going to make good financial sense for the average family. Alternately, a hotel or small high-rise building with constant hot water usage should make perfect sense.
The problem I see is consumer awareness. Think about it this way – it just took me almost 1000 words to explain why it’s important to have one home appliance in instead of three. Actually, make that four if you have a pool heater.
People generally don’t comprehend the technology or maybe they just don’t care. We need something else thrown into the pot for the masses to see the importance of MCHP, and what ever that something else is, remains to be seen.