Tag: electric home

Two-flat journal 6: How to make an all-electric house

After the bill drama with Peoples Gas last year, in which I was billed a $50 “base” fee per unit per month for the privilege of having a gas line to my house, I decided to make the gut rehab of my two flat all electric. I think that making an all electric house is easy, but it takes a lot of research to know what that means and how to select materials and appliances.

Read all of the “Two-flat owner journal” entries

Why go electric?

I have several reasons for keeping natural gas out of my house:

  • Natural gas has point source emissions causing indoor air pollution that need to be vented and evacuated properly (gas stovetops emit methane into your kitchen, so turn on your hood that hopefully vents to the outside)
  • The price of natural gas is not falling as fast as electricity is falling
  • Electricity is more and more likely to come from renewable sources, especially in Illinois because of our state policies that require ComEd and Ameren to buy more and more power from renewable sources
  • A future photovoltaic solar panel array could be integrated and some of the electricity in the house would come from its own generator
  • Without gas pipes in the house, there is less infrastructure to build and maintain

There are still some downsides to having an all electric house, namely when the power goes out on the block then nothing in the house will turn on. There are solutions, for this, though, including integrating a battery pack or using a fossil fuel-powered generator with its own tank.

The Passivhaus-certified single-family house in Hyde Park that I toured in 2018 has a small natural gas-powered generator in the rear yard, fueled by a typical Peoples Gas supply line.

What does it mean to have an electric house?

I think there are three categories of choices that one makes, about visible appliances, invisible appliances, and heating and cooling.

A visible appliance is one you use directly and frequently, like an oven and a clothes dryer. These are essentially the only two appliances that have gas and electric versions and electric versions are just as commonly available as gas version.

An invisible appliance is one that’s in a closet or in the basement, like a water heater. Most people I know have a gas-powered water heater (usually a tank, not tankless), and there are two kinds of electric water heaters (which I detailed in Two-flat journal 3). Again, these are very common and electric water heaters (standard with resistance heating, tankless, and hybrid heat pump) can be picked up anywhere a gas-powered water heat can be purchased.

Heating and cooling is the complicated category of the three. A typical new construction house or condo has gas forced air for heating, a condenser for air conditioning, and the air is pushed through the house via ducts. In the electric universe, however, mini splits/air source heat pumps have been around for 40 years and are extremely efficient at both heating and cooling. In cold climate region 5, where Chicago is, air source heat pump manufacturers have additional products to deal with the extreme cold temperatures.

Going electric in the heating and cooling category is the only one that necessitates deeper research on windows, wall assembly, and insulation to go beyond the basic energy efficiency code (Illinois Energy Conservation Code 2018). While the air source heat pump is efficient (some have a coefficient of performance, COP, of 3-4, meaning it transfers three to four times as much heat energy to the house as the energy they consume) it will work very hard to keep a house warm during negative temperature days (F°) and thus it’s important to have a well-sealed house so the conditioned air you’re paying for doesn’t escape.

If you want your house to be all electric, a lot of these choices can be made over time. For example, you can stop the air pollution by buying a range with an induction cooktop, which is extremely efficient, safe for households with children, and very easy to clean. I like to cook soup in my Dutch oven (which is compatible with induction cooktop) and I would rather not have to have the burner on for an hour, accompanied by a noisy vent fan.

Financial benefits of an all electric house

In addition to certain federal tax credits for replacing certain appliances, which you can claim when you file your tax return, there are often local incentives. ComEd has a new Electric Homes program that offers $4,000 cash (to the builder or general contractor) for an electric house (new construction or renovation) that meets their requirements. (2021 is the second year in operation, and there’s no guarantee it will operate next year.)

From ComEd’s marketing:

Building your clients’ dream homes – why not make them energy efficient?

ComEd provides a $2,000 incentive per home for electric homes new construction! All-electric home construction can sound daunting at first, but with the knowledge and help of ComEd, you too can benefit from tight envelope, all-electric HVAC, heat pump water heating, lighting and appliances. Construction of single-family homes, duplexes, townhomes, and 2-4 flats are eligible.

Make the jump to high-quality, next-generation, electric homes. Reduce energy bills while providing superior comfort. Prepare for a clean, resilient energy future.

Learn about additional clean energy strategies like solar power, electric vehicle charging, smart homes and induction cooking.

Please reach out to Sophia Seol SSeol@slipstreaminc.org if you have any questions.

I’m planning to buy these products

I’ve done a lot of research on appliances in all three categories because my architect needs to know exactly which appliances I’m selecting so the kitchen, utility closet, basement, and other spaces can be designed to fit them. Thankfully, a lot of appliances have similar dimensions so it’s easy to match the available space with the catalog of laundry machines, refrigerators, etc.

My architect and I reviewed a printed set of plans last week, mainly so he could alternate between drawing on AutoCAD and marking up issues.

There are two main attributes to watch for when selecting electric appliances: the yellow Energy Guide label that estimates the annual cost of operating the appliance, and whether it has Energy Star certification. One of the ComEd Electric Homes requirement is that every appliance that can be Energy Star certified is – I’ve found that there are no certified ranges.

My favorite place to shop for appliances online is Abt. When I polled my Twitter followers last summer for appliance store recommendations, Abt was overwhelmingly the most recommended store.

Note: I have no idea which ones will be in stock when it comes time for me to buy any of them, but these are the ones I would pick right now.

All appliances and equipment are Energy Star-certified except where noted.

Visible appliances

  • Dishwasher. I’ve got three options on my list (each costs less than $500):
  • Refrigerator (a different one for each dwelling unit)
  • Oven/stovetop/range
    • Frigidaire FCRE3052AB ($629) – Not Energy Star certified, not induction
    • Frigidaire GCRI3058SS ($1,169) – Not Energy Star certified, yes induction

Invisible appliances

  • Water heater. Something to know about tankless is that it’s not necessary to have a single tankless source for the whole house, as it’s possible to have multiple tankless water heaters at each water source, sized to the need – the kitchen sink can have one, and the shower and the lavatory can share another. The hybrid heat pump water heater currently has a 10% federal tax credit, up to $300.
    • Rheem brand’s “Performance Platinum 40 Gal. 10-Year Hybrid High Efficiency Smart Tank Electric Water Heater” (Home Depot)
    • Each dwelling unit will have the same water heater but may not have the same kitchen and laundry appliances.
  • Clothes washer. Stacked, to save space, from (each is about $800):
  • Clothes dryer. Stacked, to save space, from (each is about $800):

Heating and cooling (HVAC)

Mini split systems have two parts: An outdoor condensing unit and one or more indoor fan units. They’re connected by a refrigerant line, an outgoing condensation line, and electricity from the outdoor unit to the indoor units that is routed through a small diameter (3″) hole in the exterior wall.

Three outdoor heat pumps on the roof
Three larger-capacity heat pumps on the roof of a new construction and all-electric three-flat in Pilsen. Photo: Steven Vance.

There are several options for indoor units: Wall-mounted, ceiling mounted cassette, ceiling mounted box, and ducted (the outdoor unit will provide the hot or cold refrigerant and the ducted unit will blow air through a duct network). My architect and I have selected two ceiling-mounted cassettes per dwelling unit; these fit within the 16″ between joists and avoids the protrusion of wall-mounted units.

  • Outdoor unit, Mitsubishi MXZ-3C30NAHZ2 (Ecomfort, $3,365 x2)
  • Ceiling cassette indoor unit, Mitsubishi MLZ-KP09NA (Ecomfort, $895 x4)

I will need a venting system to exchange fresh air into each dwelling unit, without relying on the typical situation where the leakiness of houses brings in fresh air. An energy efficient way to do this is to use an “energy recovery ventilator” (ERV) that transfers the heat or chill of outgoing conditioned air to incoming fresh air to reduce the amount of energy that the heat pump would expend to warm or chill the incoming air.

An alternative to ducted ERVs is to use a wall-mounted model, such as the Zehnder ComfoAir 70 ventilation unit, Holtop ERVQ-B150-1A1F, or Blauberg VENTO Expert A50-1 W (that’s on Blauberg’s German-market website, and that company has a subsidiary called VENTS that has an American-market website). There’s also Panasonic’s WhisperComfort ($420) that can be mounted on the wall or ceiling. However, I need to verify that either has air moving capacity required by the indoor air quality standard ASHRAE 62.2, specified in the ComEd Electric Homes program. It might be possible to use two of these, including one in the bathroom.

What’s missing

Oh, one more thing, the electrical panels in the basement will need to be replaced (which is part of the replacement of the entire electrical system), and ComEd will likely need to string higher-amperage lines from the alley overhead power lines to the house. This area requires more research and possible a conversation with an electrical contractor or ComEd. I’m currently assuming that I can specify that the electrical contractor will handle this with ComEd.

Two-flat owner journal 3: Choosing the right water heater

Read all of the “Two-flat owner journal” entries

This journal entry is all about the several hours of time I spent researching which water heaters to buy for my two-flat. While my architect works on drawing the plans, I am doing a lot of research to answer questions for him, so he knows what appliances are going to be hooked up to the house’s mechanical systems.

I started researching water heaters on a cold Saturday in January so I could fill out the “appliance schedule” for the project. My first journal entry was about my new distaste for Peoples Gas. Since then, my view has evolved and we (my architect and I) are designing an all-electric house.

SCROLL DOWN FOR THE RESEARCH – Read on while I discuss my thoughts about electricity and natural gas as a power source for homes.

Discussion

Let me step back a moment. I also have a “distaste” (a weird word to use when talking about something that would literally kill you if you drank it) for fossil fuels, too. When I approached this research task I thought that an electric tankless water heater had some kind of inherent efficiency over an electric or natural gas-powered tank type.

But it doesn’t, and that’s partly dependent on how much water a household uses. Tankless water heaters are sometimes marketed as providing “unlimited” hot water, which scared me. Since I don’t go to an office anymore (because of COVID-19 and because I quit my office-attached job), I take a shower every other day. And they’re long. Just imagine that your shower never ran out of hot water. I might not get out. So that’s a personal critique of the type of water heater.

(Another con of tankless water heaters: When the electric is off, water cannot be heated; with a tank water heater, there is always residual hot water in the tank, which can still flow. Additionally, electric tankless water heaters have special electrical box requirements because they draw so much electricity.)

Let’s talk about the fuel. Natural gas is cheap right now – to purchase. But it has awful costs elsewhere, namely its contribution to pollution and carbon dioxide emissions when burnt. Burning it in the home also releases additional gases, which is why I think you should run your range hood vent/exhaust when you cook food on the stovetop.

Gas stoves emit a host of dangerous pollutants, including particulate matter, formaldehyde, carbon monoxide, and nitrogen dioxide. 

Mother Jones, “How the Fossil Fuel Industry Convinced Americans to Love Gas Stoves”, by Rebecca Leber, FEBRUARY 11, 2021

Going electric in the kitchen is pretty easy, I think. I didn’t do much research and I picked out all Energy Star-certified appliances. For cooking I chose a range with an induction cooktop and an electric convection oven (which means there’s a fan inside to blow the heat around for even cooking). Induction cooktops, while being a really efficient user of energy, have cooking benefits: Water reaches a boil faster, the surface is easy to clean, and there are fewer burns because the surface doesn’t get hot.

Creating an all-electric house is pretty easy, actually, until you get to the heating and cooling part, and knowing how to heat a house with electricity in the very cold climate of northern Illinois requires even more research.

Water heaters are actually easy to figure out (after 5 hours of research) because, in the end, all you do is plug them in to a 240 volt receptacle and connect to the already-existing water pipes.

I am still in the middle of researching electric heating and cooling and I’ve opened a conversation with two HVAC contractors (one that sells Carrier and one that sells Mitsubishi).

Water heater research

I originally tweeted all of this on January 16, 2021, because I like using Twitter as a sounding board.

I have researched five types of water heaters because I want to fully understand the purchase price and energy price of each.

  1. Natural gas, tank
  2. Natural gas, tankless
  3. Electric, tank
  4. Electric, tank (hybrid w/heat pump)
  5. Electric, tankless 

Based on my research of manufacturers’ reported “Energy Guide” stickers (the yellow stickers required by federal law) for these five types, the Electric, tank (hybrid w/heat pump) (option 4) is far and away the most efficient water heater. 

The Electric, tank (hybrid w/heat pump) has an annual operating cost of $104. What is this thing? It takes the standard tank, uses electric heating elements (think of the wires inside your bread toaster), and extracts heat from the air in your house with the heat pump. That’s pretty amazing: There is free heat to be extracted from the air.

The Electric, tank (hybrid w/heat pump) has less than half the operating cost of the next lowest type: Natural gas, tankless.

Rheem (a water heater manufacturer, which also owns the Richmond brand) says that an electric tank water heater with hybrid heat pump uses less electricity than an old-fashioned incandescent light bulb.

Note that the electrical prices in the yellow “Energy Guide” sticker is 12 cents per kWh, and ComEd just charged me ~7 cents per kWh, so the annual operating costs of electric are less than the stickers say. 

Next, as part of the “total cost of ownership” (well, minus maintenance) I added in the purchase price. The Electric, tank (hybrid w/heat pump) costs $1,400. That’s 1.5-4x more expensive than the other types of water heaters!

However, I’ve since found that Rheem/Richmond makes a couple cheaper models that don’t have high-tech features, so the purchase price is anywhere from $1,000 (if you can find that model) to $1,175.

I calculated the “5 year cost of ownership” price for water heaters of each type because it makes sense to distribute the purchase price over a period of its lifetime. I could have easily made this a 10-year amortization since water heaters come with 6 to 12-year warranties. I interpret the length of the warranty as the manufacturer’s assessment as to how durable they’ve created the machine.

How they compare

Of the five types, I compared 11 machines (view the comparison chart).

The cheapest water heaters over five years are: 

  1. Electric tankless
    $1,479 (caveats in that annual energy cost was extrapolated because a direct Energy Guide sticker wasn’t found)
  2. Electric, tank (hybrid w/heat pump)
    $1,695 (does not include federal tax credit)
  3. Natural gas, tank
    $1,999

Remember, though, that the Energy Guide stickers for the electric water heaters use a 41.7 percent higher energy cost than ComEd currently charges, and ComEd offers hourly pricing so the price can be much, much lower per kWh and the prices for the electric water heaters are EVEN LOWER. (Thank you for pointing this out, Troy.)

Guess what…the price of the Electric, tank (hybrid w/heat pump) can come down even more because of (1) a ComEd rebate, and (2) federal tax credit worth 10 percent of the purchase price + installation, up to $300.

Bonus: By getting electric you are part of the carbon-free future. 

Further discussion

Now that I’ve convinced you that an Electric, tank (hybrid w/heat pump) water heater is the cheapest option, here are a couple of other things that came up in the Twitter conversations.

  • Including utilities (i.e. electricity cost) in the rent for the rental apartment in my two-flat benefits both me and the tenant. The tenant has a fixed and predictable energy cost and fewer bills to pay, while I am able to charge a bit more than I predict the cost will be in order to pay back the higher upfront costs of the water heater and the Energy Star-certified appliances (as well as the heating and cooling system).
  • The calculations might be different if I looked into having individual tankless water heaters at the point of demand, or using them as “boosters”. Tankless water heaters come in a variety of capacities and energy outputs (measured by how much energy it takes to increase the temperature from how cold the water is when it enters the house or heater to the desired temperature). One could be added to the kitchen, the bathroom, and next to the laundry, and sized for the differing demands of each location.
  • A complex system could be built that is programmed to buy energy from ComEd when the hourly cost is the lowest and use the power from the battery when the hourly cost is highest.
  • A couple people asked about geothermal. I looked into it and I wrote it off quickly: A drilling rig needs to access the yard to drill multiple horizontal wells. The garage blocks that from happening. However, an apartment building renovation in Rogers Park designed by PMP Architects is converting its heating system to use geothermal energy.