Recently a Twitter storm erupted over new Federal air conditioning guidelines. Seems like the Federal Government is clueless about the subject. Consumer Reports chimed in. Unfortunately, they also are clueless. Fortunately, Heat With Wind gets it right.
Most people in the air conditioning business realize that air conditioners are more efficient when the outside air temperature is cooler. Air conditioners are more efficient when the outside temperature is 80 degrees outside as opposed to when the temperature is 95 outside. It is better to drive down the temperature in your house at night because it is cooler outside at night than during the day.
Utility industry experts realize that energy use during peak hours is not only more expensive, it is worse for the environment. It is better to drive down the temperature in your house at night, especially around 1 AM, when the price is lower and the grid is not stressed.
Home energy experts realize that dehumidifiers, what all
those people with open windows are uselessly using all summer when their
windows are open, are not necessary when the homeowner uses a properly sized
air conditioner. It is better to use a
properly sized air conditioner every day and never open your windows than to
use a dehumidifier.
Also, if you keep the shades down on the sunny days, your
house does not heat up as much during the day, making pre-cooling work better. You will keep more comfortable if you don’t
let the heat in in the first place, and you are not using heat generating appliances,
like dehumidifiers, during the day.
The Heat With Wind guideline is as follows:
To keep the humidity level in your house low, in order to
eliminate the need for a dehumidifier, we recommend to never open your windows
during the summer. Instead, use the air
conditioner every day. Air conditioners
dehumidify the house eliminating the need for dehumidifiers.
Next, we recommend that energy conservation measures are
taken to minimize the heat gain of your home during the summer. This can be done by upgrading your appliances
to the most efficient available, using sun blocking shades (black outs) and
planting sun blocking trees and shrubs.
Sun blocking windows are not recommended in cold climates. And never, ever, ever use a dehumidifier.
Next we recommend driving your house temperature down to 70
degrees at night then shutting the air conditioner off from about 11 am to 7
pm. Because you pre-cooled, your house
will remain comfortable the whole day.
This strategy is the lowest cost strategy and it is the best
for the environment. It is also the most
comfortable strategy. Plus, because the
humidity level in your house will be on average much lower than any other
strategy, there will be less mold in your house-your house will not stink and
you will be healthier.
Some people consider the electricity grid to be horrible. Certainly no one wants a coal plant in their community. But the grid is changing-there are a lot of great things about the grid. The saying “Don’t throw the baby out with the bath water” applies. A little history will help put things in perspective.
September 4, 1882 Thomas Edison fired up the Pearl Street Station in
Manhattan. This was the first commercial
power grid in the U.S. and served 82 customers. This grid was powered by coal.
Exactly 26 days later, a second Edison grid became operational in Appleton
Wisconsin. That generation system was a
hydroelectric dam. Except for the first 25 days in the history of the grid, the
grid has never been 100% coal.
The first coal plants were terribly inefficient. The early turbines had an efficiency of about 1.6%. In the 1910’s the efficiency was a whopping 15%. At that efficiency, generation of a kilowatt hour of electricity would release 6.68 pounds of CO2, in addition to a lot of other toxic garbage.
as mentioned earlier, except for the first 25 days of the grid, coal has NEVER
been the only source of grid energy. Today
the grid energy supply is diverse (think wind), with the share supplied by coal
decreasing every year. Today, coal
supplies only about 28% of the electricity we use. The trend from the very
beginning has been for emissions of CO2 per kilowatt hour to drop as utility
operators found ways to use less fuel and spend less money. Emissions on our grid, which is managed by
Jersey-Maryland), for the year 2018, were .924 pounds CO2 per KwH. That is quite different from the 6.68 pounds
of CO2 per KwH of the 1910’s coal generators.
In fact, today, about 39% of the electricity we use (PJM grid) comes
from zero carbon emitting sources of generation. And things are getting better. Think of all the people putting solar panels
on their homes and consider how wind power is now the least expensive
generating option. This trend will
continue. The following graph shows how emissions of CO2 per KwH have fallen
since 2008 on the PJM grid.
other trend has been that, in real dollar terms, the price of electricity per
kilowatt hour has steadily decreased.
The Energy Information Agency, EIA.gov, which is a division of the U.S.
Department of Energy, expects little or no price change in electricity cost
bottom line is that the electric grid is getting cleaner every year, it became less
expensive over time and is expected to remain at about the same price though
Natural gas, however, is a different story. Natural gas chemistry cannot change so natural gas cannot get cleaner. It will always emit 11.7 pounds of CO2 per Therm when burned. When burned, it releases about half the CO2 that coal does. Maybe that seems great, but remember, half of a really big number is a big number. Also, natural gas is a potent greenhouse gas that leaks in large amounts throughout its distribution system. According to the Energy Information Agency, natural gas prices are expected to increase by about 66% by 2050. Because natural gas is a horrible fuel, many of us hope that natural gas will be taxed as a carbon emitting fuel, making it even more expensive. Not only that, the infrastructure to bring natural gas to homes is in poor shape and is very expensive to repair. Ultimately the gas customers will need to pay for the repairs. Bottom line, natural gas will never be clean, and it is getting more expensive.
My Results and Myths About Electric
Heating and Its Cost
As an Actuary, I’ve always have been very keen about saving money. It should be of no surprise, then, that I know how to get the best electricity rates. Since 2007, when it was first available, I have been on ComEd’s Hourly Pricing Program. On this pricing plan, I pay hourly wholesale rates. These rates are insanely low. Next, when you shut off your gas, ComEd gives you an electric space heat discount of $.01773 per kilowatt hour for all kilowatt hours used, be they used for heat or charging an electric car. The net result is that I only pay about $.065 to $.070 per kilowatt hour, including taxes. I didn’t know about the space heat discount initially. I learned about it a few months after the switch. Then, when I did sign-up for it there was an approval delay. For the first year, 2014, I did not get the discount. The top graph below shows my actual energy costs as recorded in Quicken while the second graph is what I would have paid had the electric space heat discount been applied from day one. Only year 2014 was affected by this.
My mixed fuel years total cost is in blue and my all
electric years total cost in green. Looking at the graphs, did my expenses go
up or down? Clearly, my expenses went down.
Myth #1: Heating with
Electricity Costs More than Heating with Natural Gas
Most of the dollar savings shown above are due to reduced
gasoline expenses. However, for my
house, heating with electricity costs less than heating with gas. To show this clearly, we will answer the
question whether switching to gas heat would have saved me money last
year. Here is a detailed analysis using
data from the ComEd billing cycle of January 19, 2018 to January 18, 2019:
of Why All Electric Heating Saved Me Money 2018
This chart shows all the costs that would change had I to switched to natural gas heating last year. Start with my current total electricity cost for the period 1/19/2018 to 1/18/2019. Subtract items where costs go down, like the cost of the kilowatt hours needed to run the heat pump and the extra customer fee I pay for being all electric. Then add items where my costs go up, like the $.01773 per KwH discount I lose on non-heating electricity use. Finally, add the cost of running a gas furnace, which includes the customer fee, the fuel cost and the cost to run the furnace fan. As you can see, switching to gas heat would not have saved me money. Obviously, the converse is true:
I Saved $229.24 Heating
with Electricity from 1/19/2018 to 1/18/2019!
Let that sink in for a moment: For five years in a row, for
my 2600 sq. ft. home in Lake County, Illinois it has cost me less to heat my
home with electricity than it would have had I heated with natural gas. Think
of the solar panels I could buy with the savings! Think about how I could use that money to
make my house more efficient. Like compound interest, the savings would grow.
Myth # 2: Heat Pumps Do
Not Work at Temperatures Below 20 Degrees.
This graph of Chicago weather shows the average number of
hours annually (vertical scale) within each temperature band (horizontal
scale). We spend quite a bit of time below 20 degrees. If heat pumps could not work below 20
degrees, people trying to stay warm with a heat pump in the Chicago area would
be in trouble.
This graph shows my heat pump’s heat output (thick green
line) for a house with my heating capacity requirement (black line). Remember that my heat pump is an air source
heat pump, not an expensive geothermal heat pump. Pretty sure the graph shows that my heat pump
works down to at least minus ten. The Rockford graph shows it working down to
minus 20. My heat pump provides 100% of
my heating needs above 5 degrees. Pretty
sure the myth has been busted.
Myth #2 Busted!
Graphs produced by Carrier.
Myth #3: Heating with
Electricity Is Worse for The Environment
Earlier, I showed the PJM CO2 emission trend line for 2008
Notice that since 2008 the graph is trending down. In fact,
grid CO2 emissions per KwH are down 24.2% in the last ten years. This trend will continue in the future as
coal plants continue to close, wind power is added to the grid, gas generation
facilities improve in efficiency and other technological advances occur. So, even if electric heating were worse
today, that disadvantage would be short lived.
Let’s look at my annual CO2 emission trend. Here are my results since 2010:
It’s interesting that this graph is very similar to my total
cost graph. I’m pretty sure the less money we spend, in general, the less environmental
damage we do. Regardless, my emissions
have declined every year since going all-electric, except for the slight uptick
last year. As with the annual cost, most
of the reduction is due to lower gasoline emissions. Let’s now look more
specifically at my home heating results from last year.
From the earlier table we saw that my heat pump used about
9600 KwH to heat my home to about 70 degrees from January 19, 2018 through
January 18, 2019. Using the PJM annual
CO2 emission rate of .924 pounds of CO2 per KwH, CO2 emissions for heating my
house was 8,870.4 pounds.
Heating CO2 Emissions
Gas Heat: 9226.5
Electric Heat: 8870.4
Had I heated with natural gas, I would have used 757 therms
of natural gas and about 400 KwH to run the furnace fan. Since burning a therm of natural gas releases
11.7 pounds of CO2, the CO2 from using gas heat would have been 9226.5 pounds.
For the period in question, January
19, 2018, through January 18, 2019, Myth #3 has been busted!
However, the results of this calculation vary significantly
with the weather. On an average year my
heating system will be better environmentally than a natural gas system. Keep in my, though, that the grid will get
cleaner in the years to come.
Eventually, regardless of weather changes year to year, my system will
forever be better environmentally than a natural gas system.
Myth #4: My Heating
System Cost More Than a Comparable Traditional System
My heat pump is an air source heat pump that operates
similarly to a central air conditioning system, however, it also provides heat
in the winter. It cost about $2000 more
than a comparable air conditioning only unit.
But I saved $2000 by buying an air handler instead of a furnace. Since
the net cost of the two systems is the same, my system could not have cost
more. (This information is from the original system quote and a recent
discussion with an installer)
Myth #4 Busted.
What About the Other Electric
The other components of my home that were once powered by
natural gas are the ventless heat pump water heater, the ventless condenser
clothes dryer, and the induction range.
These appliances are all more efficient than their gas
counterparts. They cost less to run and
are better for the environment. And,
they are just as convenient, if not more so, than their natural gas
The Problem with Refrigerants
Some heat pumps contain refrigerants that are potent green
house gases. My heat pump uses
R-410a. This refrigerant is being phased
out in Europe in favor of R-32. R-32,
when leaked, has much less impact on the environment than R-410a. Honeywell
Solstice (R-466a) has also been developed as a replacement to R-410a. There is
continuing research on building better air conditioners and heat pumps. I encourage everyone to pressure their
elected officials to accelerate the phaseout of refrigerants with a high
GWP. There are some success stories of
companies that have redesigned heat pumps to us use better refrigerants.
Mercedes Benz, for example, is using CO2 as a refrigerant in the air
conditioners of their cars. For all the
success, though, we can do better. That
said, there is no reason to preclude you from installing a heat pump for your
HVAC system or a heat pump water heater. Why?
The alternative, heating with natural gas, requires the use of natural
gas, itself a potent greenhouse gas.
Methane leaks from the gas industry dwarfs the problem with current
refrigerants. We need to move away from
using natural gas.
Reasons to go All-Electric (And Live
Electric homes cost less to operate
Electric homes cost less to build
The money saved on going electric can be used to
purchase solar panels, insulation or wind power
Heating with electricity makes wind power more
profitable since more heating is done at night
Solar energy installers love all-electric homes
because larger arrays are easily justified
Because there are no open flames, all-electric
homes have cleaner air
Because all-electric homes have better humidity
control there is less opportunity for mold growth-so, all-electric homes smell
Going all-electric will stimulate innovation in
the associated electric appliances, leading to more efficient and reliable
appliances in the future
The increased winter demand on the grid will
stimulate innovation on the grid infrastructure making the entire system more
The grid will be much more efficient in ten
years-the appliances you buy today will be used on that grid meaning the
electric appliances you buy today will become greener as they age
Electric homes, unlike mixed fuel homes, have
zero risk of carbon monoxide poisoning
Electric homes will not blow up due to gas leaks
Electric homes have less risk of kitchen fires
and burn injuries because there are no flames
Electric induction ranges do not add toxic air
into your home as do gas ranges
Induction ranges are way sexier than gas ranges
Electric ventless dryers, do not have vents that
clog up with lint, i.e., they don’t have that fire risk
Electric dryers and water heaters do not have
vents that insects and vermin can enter
Electric dryers and water heaters do not have
vents that draw in cold, dry air in the winter and warm, humid air in the summer
Electric homes can be powered with zero emission
sources of energy-natural gas homes cannot
Transportation dwarfs every other source of CO2 emissions, especially when you consider a substantial amount of the industrial complex in the U.S. is directly involved in creating and maintaining the transportation infrastructure. Becoming less dependent on transportation is the best thing you can do to fight climate change. Walk more, fly less, buy your food from local sources, live in a walkable community.
Ok, I’m not turning my back on wind power, but, the incentives for going solar in Illinois are too good to ignore. Within the coming weeks, Sunrun will be installing a nearly 11 kW solar energy system on my roof, which will produce about 11 kWh of electricity per year. With recent home energy efficiency improvements, together with those planned over the next 6 years, this system is projected to produce more than 100 percent of my household energy needs, along with a good chunk of what I need to power my Chevy Volt. Plus, federal and utility incentives, along with the fantastic financing available, make this system a financial win from day one!
Let’s consider the federal tax incentive first. Since 2005 solar panel installations have been incentivized with a 30% non-refundable federal tax credit on the total cost of the installed system. Non-refundable means that to receive the full credit, your federal income taxes for must equal or exceed the amount of the credit. If the credit is more than you owe in the year of installation, it may be possible to carry over the excess credit to the following year’s tax bill. Regardless, your tax bill has to be greater than or equal to the credit to take advantage of the full credit. So, the credit is not fully available to everyone. For my system, which has a gross cost of $29,000 the tax credit is $8700. Since this is less than my federal taxes for this year and next, I can take advantage of the entire credit. This brings my installed cost down to $20,300. Note that this credit is being phased out starting in the year 2020. Keep that in mind if you are planning to install a solar panel system.
Next, let’s consider the utility incentives. Owners of solar energy systems in Illinois are eligible to receive solar Renewable Energy Certificates (sRECs) for the energy they produce. Renewable Energy Certificates were conceived in the 1990’s to incentivize investment in renewable energy facilities. A Renewable Energy Certificate is awarded to the owner of the renewable energy facility for every Megawatt hour of energy produced. These RECs can be sold to the utilities as part of a Renewable Portfolio Standard law in the state or they may be sold on the open market. Individuals or institutions wanting to claim that their electric energy comes from renewable energy can buy these certificates on the open market or through REC dealers in quantities to match their electricity consumption. This also is the mechanism by which green energy suppliers claim to provide you with green energy-they simply buy power from your local utility or on the open market, then add on the cost of the REC, along with their own marketing and profit charges. It is usually cheaper, by the way, to buy your own power from your local utility, then buy your RECs on the open market or from a REC dealer.
The Illinois Future Energy Jobs Act of 2016 changed the way in which solar energy system owners are compensated with sRECs bought by the utilities of the State of Illinois. As noted before, utilities must buy RECs to satisfy their Renewable Portfolio Standards obligation. The prices per sREC are set by the Illinois Commerce Commission, but now, instead of getting paid as the facility produces power, new system owners are paid up to 15 years’ worth of SRECs in advance of production in a lump sum. Since an sREC is currently worth $72.97, 15 years of SRECs is worth $1094.55. With a production estimate of 11 kWh per year, my lump sum would be 11 x $1094.55 = $12040.05. I would need to pay a 10% commission on this to sell them, so, my net lump sum would be $10836.04. My net system cost is now only $9463.96. Not down to zero cost, but, there are more incentives.
The installed system will generate electricity that will offset my actual electricity use, thereby saving me money. Since my system will be eligible for net metering, and, will be grandfathered under the net metering rules for the life of the system, ComEd will credit me for all power generated, including the delivery fee, up to the amount of energy I use. Assuming 11000 kWh at $.09 per kWh, my savings today would be about $990 per year. With inflation the savings per year will increase. Everyone would agree this income stream has value. To calculate the value, I assume a 5% discount rate and a 3% inflation rate. Using these assumptions the savings income stream is worth $22785.12. Subtracting this from the system cost calculated in the previous paragraph, on day one there is a net gain of $13321.16. Of course there will be maintenance costs. How much is the $64000 question. I doubt theses expenses will exceed $13321.16. The worst case scenario is that the roof will need replacing and all panels would need to be removed then reinstalled. Aside from that, any other expenses are fairly minimal. Currently, my roof is in great shape and I am not expecting a roof replacement for quite some time. Only time will tell, but, my guess is that the present value of expenses will not exceed the day one gain calculated above.
Basically, I am getting paid to put solar panels on my house. Not a bad deal. Not a bad deal at all.
Back in late 2013, my natural gas furnace and air conditioner broke down beyond repair and needed to be replaced. A decision had to be made: replace them with a traditional natural gas furnace and air conditioner or replace them with an air source heat pump with electric heat strip back up. Since I live North of Chicago in a 2600 sq. ft home, I was advised against going all electric. I was told that I would freeze or that my costs would go up substantially. Also, I was told that electric heating was worse for the environment. The research I had done showed otherwise on these points, so, I opted for going all electric and getting off the natural gas grid. (See previous article for new system details). At the same time, I traded in my Toyota Corolla for a Chevy Volt.
There was a learning curve in using the new equipment. The Volt, for example, will turn on the gasoline engine at one of two temperatures to assist with heating the interior of the car. The higher setting, at 35 degrees, uses more gas than the lower setting, at 15 degrees. The default is 35. It was several months into the first winter before I realized that the setting existed – the controls on the Volt are a lot more complicated than on the Corolla. Setting the heating assist temperature to 15 cut my gasoline use substantially.
With regard to the heat pump, there are also many controls which effect the amount of energy used. As with the Chevy Volt, it took some time to understand the optimal settings for the unit. Additionally, I was not aware that, as an all electric customer, I was eligible for a electric space heating delivery charge discount of $.0125/kwh from my electric company. It was not until recently that I could get an accurate comparison of annual costs and emissions of the old system vs. the new system.
Below is a table showing the costs and emissions associated with three different approaches. Scenario one assumes all traditional gas appliances and a Toyota Corolla driven about 10,000 miles. Scenario two is the same house but with a Chevy Volt, also driven about 10,000 miles. The last column shows my actual results for an all electric house (there is NO gas connection!) and a Chevy Volt driven about 10,000 miles. In all three cases the house is assumed to be kept at 72 degrees year round with no additional heating sources and two occupants, including a teenager with friends over regularly.
Year Ending 9/16/2016
The costs and emissions for the Gas Furnace systems assumed 845 therms spread throughout the year based on my previous use patterns and heating degree days for my zip code (60030) as provided by weatherdatadepot.com. Costs were derived from rates provided by Northshoregasdelivery.com. Costs for the electricity included under the traditional columns is my previous estimated cost of $489 for the year. For those two columns, emission calculations assumed 4500 kilowatt hours of electricity per year. Emissions per therm are a standard rate of 11.7 lb. per therm. Electricity CO2 emissions are 0.964 lb./kWh as stated in ComEd’s Environmental Disclosure Statement for March 31, 2016.
The Corolla was assumed to use 367 gallons of gasoline. CO2 emissions per gallon of gasoline is assumed 19.6 lb. per gallon and average cost of $2.20 per gallon was assumed. The gasoline use of the Chevy Volt for the year was based on an actual expense of $99 with an average cost of $2.20 per gallon. Energy used for charging the Volt was about 4100 kWh for the year.
Costs and emissions shown in the last column were from actual bills with electricity use of 18,284 kilowatt hours. Because I use ComEd’s Real Time Pricing, I purchase my electricity at very low wholesale rates. With this program my gross rate, that is after taxes, customer fees and delivery, is about $.08/kWh. The costs shown do not include renewable energy certificates which effectively drop the emissions to zero. Voluntary wind renewable energy certificates are currently about $.02 per kilowatt hour. For my electricity use this would equal about $360 and would effectively make my electricity emission free.
The primary reason converting to an all electric system is that as more zero carbon energy sources added to our grid, the closer our grid will get to being 100% renewable and emission free. The emissions listed in the far right column for an assumed renewable grid are only 745 lb whereas, even with a 100% renewable grid, staying on the natural gas grid leaves me with an unacceptable CO2 emissions of 10,631 lb. We cannot make the natural gas grid emission free. Our electric grid, however, is getting better. Both solar and wind are getting less expensive as is storage technology. By using an all electric system today, my emissions are lower as are my costs. As time goes on our electric grid will move in the direction of an all renewable grid. Things are getting better!
Sure, we are all impressed with Elon Musk and his Tesla cars. And now he has created quite a buzz with his Tesla Powerwall battery. Impressive. And expensive. The total investment for the 7 kilowatt hour (kWh) system is estimated to be $7,140 installed. The battery is guaranteed ten years. And you save at most $255.50 per year using it every day, assuming 7 kWh per day with a $.10 per kWh spread between charge and use. Over the ten year warranty period you make back $2,550 of your $7,140. Ouch. There are, however, more mundane products that provide a better investment and have a more positive impact on the environment. I’m talking about the rather mundane electric heat pump.
Heat pump? Good luck selling that idea. You may see celebrities and tech gurus driving around town in a Tesla. But it is a little bit difficult to drive around in a heat pump – let alone look cool while driving one. Getting the word out that electric heat pumps are a better option for home heating (and high efficiency cooling – they do that, too) than is a natural gas powered furnace is not easy, especially without the high profile cheerleaders. The benefits of heat pumps, however, are great, including low cost of operation. And, in terms of environmental benefits, no other consumer product, not even solar panels or the Tesla electric car, beats heating a home with a heat pump powered by grid sourced wind power. The reason is that natural gas has some serious issues that heating with wind avoids.
For one, natural gas is a very potent greenhouse gas. Pipeline leaks releasing methane are common – and sometimes lead to explosions. Second, production of natural gas, especially when produced by fracking, is associated with severe water pollution. Finally, natural gas emits a lot of carbon dioxide when burned.
Until I shut off the gas and got off the natural gas grid, natural gas use in my 2,600 sq. ft. home was responsible for an average 10,641 pounds of CO2 emissions annually, or about 44% of my total CO2 emissions. My auto CO2 emissions averaged 7,300 pounds each year, while my household electricity use contributed only 6,520 pounds. This scenario is the same for many other people in the Chicago area, where I live. Carbon dioxide emissions from burning natural gas is often the greatest source of CO2 emissions for homeowners. This is somewhat troubling in that natural gas is being marketed as a clean fuel – it is not. It is possible, though, to effectively bring household CO2 emissions to zero.
The solution is to replace natural gas appliances, only after they break down beyond repair, with the most efficient electric appliances available and then power those appliances with wind power. By waiting until the appliances break down to replace them, not only does the homeowner get the most out of the old appliances, but, as time goes by, better, more efficient appliances appear on the market. In this way, you get more for your money.
Think of it this way: The better the return on the equipment, the more money available to invest in other energy saving ventures, i.e., I will have more money to buy more solar panels in the future, thus having a more positive impact on the environment. It is generally better to wait as long as possible to replace equipment. For example, 20 years ago, when my house was built, electric heat pump water heaters were not an option. Plus, heat pumps for home heating did not have the low temperature performance in terms of efficiency or capacity to make them practical. Today, however, heat pump water heaters are the most cost effective and environmentally friendly way to heat water. And, today’s air source heat pumps are more efficient than ever. Plus, they still pump heat at minus 15 degrees Fahrenheit. Getting off the natural gas grid has never been easier!
My opportunity to get off the natural gas grid came in 2013 when my gas water heater and furnace broke beyond repair with the air conditioner looking soon to follow. My power-vent water heater was replaced by a GE GeoSpring heat pump water heater. My 125,000 BTU furnace and my 18 year old air conditioner were replaced with a 4 ton Carrier GreenSpeed heat pump with a 10KW backup heat strip. The heat strip is only used for temperatures below 5 degrees. My washer also broke down. I replaced it and the dryer with a matching set from LG. I chose this pair because they stacked and because the dryer is an efficient vent-less condenser dryer. Finally, my gas oven with a non-functional broiler was replaced by an electric convection oven with a ceramic smooth top. This will eventually be replaced by an induction oven, which is as convenient and responsive as cooking with gas.
The difference in cost between what I purchased and what comparable gas appliances would have cost was not much in total. The heat pump water heater did cost more than a power-vent unit and my electric service did need to be upgraded. The Carrier heat pump with the air handler cost about the same as had I bought a high efficiency furnace with a matching high efficiency air conditioner. The total additional cost for everything I bought was about $1,500 compared to what more traditional replacements would have cost.
So, what did I get with that $1,500 investment? First, my expenses are lower. Shutting off the gas eliminated the $300 annual gas company customer fee. Also, going all-electric lowered my electricity delivery fee by $.0125 per kWh. I also benefit from being on ComEd’s Residential Real Time Rate program. Since the heat pump is used more in the middle of the night when rates are low, my cost per kWh stays low. My average rate over the last year, with taxes and delivery included, but not including customer fees and other non-variable items, was $.073 per kWh. On average, my annual household savings are estimated to be $200 to $300 – and that is while keeping my house at 70 degrees all winter.
There are other, more subjective advantages. I am more comfortable. Elimination of the gas clothes dryer and the power vent water heater eliminated two large sources of outside, unconditioned air infiltration: I am warmer in the winter. For the same reason, the indoor humidity level is lower in the summer. Since the humidity level is much lower in the summer, there is much less opportunity for mold to grow in the house – that means better health for everyone in the house. Finally, I’m safer. There is no indoor fossil fuel consumption so there is no chance for carbon monoxide poisoning. There are no unburned hydrocarbons from a gas oven. There is no fire risk from open flames from the cook top or fire from a clogged clothes dryer vent. And, unlike my neighbor’s house that filled with gas from a gas leak, there is no risk of the house blowing up. The more impressive investment return, though, is that I can power all of this with renewable wind energy, thus reducing my CO2 emissions to zero.
Wind energy is available to anyone through the purchase of renewable energy certificates. Renewable energy certificates were developed to encourage development of renewable energy power generation. With wind power, certificates are awarded to wind producers for wind energy added to the grid. Strict accounting standards are in place to assure that the number of certificates awarded to a producer matches the amount of power added to the grid. This way the certificate holder knows that their purchase was for wind power added to the grid, primarily displacing electricity produced through burning coal or natural gas. The certificates can be subdivided and sold to utility customers who want their power to come from wind. This is the standard mechanism for which green energy companies lay claim to providing renewable energy or how corporations lay claim to being 100% wind powered.
Here’s how it works for me: I buy shares of certificates totaling 15,000 kWh per year. The shares cost me $.02 per kWh. The purchase is through a third party with no connection to my electric utility. Keeping the two transactions separate has the same environmental benefits as if I were to buy from an alternative renewable energy supplier. There is, however, a benefit to buying certificate shares separately: I am cutting out the middle man thus getting my wind power for the absolute lowest cost. Since my house, on average, will use less than 15,000 kWh per year, my house is effectively 100% wind powered and emission free. So, going off the natural gas grid saves me $200 to $300 on my regular utility bills and the extra cost for the wind renewable energy certificates is $300 per year. After my original extra investment of $1,500, the ongoing net cost for reducing my whole house CO2 emissions to ZERO is less than $100 per year (10 year cost less than $2,500). Compare that to the Powerwall ten year cost of $4,590 with no reduction of CO2 emissions: The heat pump powered by wind is the clear winner!
The trend has already been established: Heat pumps are coming down in price, becoming more efficient and are taking a greater share of the home heating market. This development, in conjunction with an increasingly cleaner electric grid, will lead to great environmental benefits. The benefits are even greater when home owners advance wind energy production by buying renewable energy certificates to cover their heating load. Winter electricity use, however, does increase dramatically, especially on very cold days, posing a challenge for grid operators. We will meet this challenge as the grid is improved and as our homes become more efficient. Using heat pumps may not be sexy, but, they are an important part of reducing our green-house gas emissions. The word needs to get out. Perhaps Tesla can get into the heat pump business. Perhaps Elon can somehow find a way to make it cool to drive one around town.