Wood Stove vs Electric Heater Seasonal Cost Calculator

Introduction

Heating costs can vary dramatically depending on the fuel you use, the efficiency of the equipment, and the amount of heat your home needs over the course of a winter. A wood stove can look inexpensive when firewood is locally available, but the true comparison depends on how much usable heat each cord actually delivers after efficiency losses. Electric heaters are easy to run and often nearly 100 percent efficient at the point of use, yet electricity prices can make them expensive for whole-season heating. This calculator puts both options on the same footing by converting your seasonal heat requirement into estimated fuel use and cost.

The goal is not to tell every household to choose one system over the other. Instead, it helps you answer a practical question: if your home needs a certain amount of heat, what would that heat cost from wood, and what would it cost from electricity? By entering local prices and realistic efficiency values, you can compare one season or several seasons and see how quickly the totals diverge. That makes the tool useful for budgeting, planning a stove purchase, evaluating backup heat, or simply checking whether a common assumption about “cheap wood heat” or “expensive electric heat” is actually true in your area.

This page focuses on seasonal operating cost, not installation cost. In other words, it compares the money spent on fuel or electricity to produce the required heat. If you are deciding whether to buy a stove, upgrade an existing unit, or rely on portable electric heaters, this operating-cost view is often the first and most useful step. Once you know the annual difference, you can decide whether equipment, maintenance, storage, and convenience factors justify one option over the other.

How to Use

Start with the seasonal heating requirement in BTU. This is the total amount of heat your home needs over the period you want to analyze, such as one winter. If you have had an energy audit, a heating load estimate, or fuel records from a prior season, you may already have a reasonable number. If not, you can still use the calculator for scenario testing by trying a low, medium, and high estimate.

Next, enter the firewood cost per cord. A cord is a standard stacked volume of wood, but the price can vary widely by region, species, seasoning, and whether delivery is included. Then enter the BTU per cord of wood. This value represents the energy content of the wood before stove losses. Dense hardwoods usually contain more energy per cord than lighter softwoods, and wet wood delivers less useful heat in practice because some energy is spent evaporating moisture.

The wood stove efficiency field adjusts the raw BTU content of the wood into usable heat delivered to the home. For example, if a cord contains 20 million BTU and the stove runs at 70 percent efficiency, only about 14 million BTU become useful indoor heat. Older stoves, poor draft conditions, and unseasoned wood can reduce real-world performance. Newer EPA-certified or catalytic stoves may perform better when operated correctly.

On the electric side, enter the electricity price per kWh and the electric heater efficiency. Standard resistance heaters are often modeled near 100 percent efficient because nearly all consumed electricity becomes heat indoors. If you are using this calculator to approximate another electric heating technology, such as a heat pump, you may choose a different effective efficiency value to reflect its performance. Finally, enter the number of seasons to compare if you want cumulative totals instead of just a single-season snapshot.

After you click Compare, the calculator estimates the cords of wood required, the electric energy required, the total cost for each option, and a break-even wood price. It also builds a cumulative table showing how costs add up over multiple seasons. That table is especially useful when you are thinking about long-term budgeting rather than only the next winter bill.

Formula

The wood calculation begins by finding the amount of usable heat available from one cord. If a cord contains a certain number of BTU and the stove captures only part of that energy, the usable heat per cord is the BTU content multiplied by efficiency. The number of cords required is then the seasonal heat demand divided by usable BTU per cord. In MathML form, the page uses the following relationship:

$C=\frac{Q}{B\times \eta }$, where $C$ is cords, $Q$ is seasonal heat demand, $B$ is BTU per cord, and $\eta$ is stove efficiency expressed as a decimal in the underlying logic.

Once the number of cords is known, the seasonal wood cost is simply cords multiplied by the price per cord. That gives a direct estimate of how much you would spend on firewood to meet the specified heat demand. If you compare several seasons, the script multiplies the single-season wood cost by the number of seasons and also shows the cumulative total season by season.

For electricity, the calculator converts the heat demand into kilowatt-hours. One kilowatt-hour equals 3,412 BTU, so the script divides the required BTU by 3,412 and adjusts for electric heater efficiency. If electric efficiency is 100 percent, the conversion is straightforward. If you enter a lower or higher effective efficiency, the required kWh changes accordingly. Multiplying the required kWh by the electricity price per kWh gives the seasonal electric heating cost.

The break-even wood price is another useful output. It answers this question: at what firewood price per cord would the wood option cost the same as electricity for the same seasonal heat demand? The script computes that by dividing the electric seasonal cost by the number of cords required. If your local wood price is below that break-even number, wood is cheaper on fuel cost alone. If it is above the break-even number, electricity is cheaper under the assumptions you entered.

These formulas are intentionally simple and transparent. They do not try to hide assumptions behind a black box. Instead, they let you see exactly how heat demand, fuel energy content, efficiency, and local prices interact. That transparency is valuable because heating decisions are often influenced by anecdote, habit, or rough rules of thumb. A clear formula-based comparison gives you a more reliable starting point.

Example

Suppose a home needs 60,000,000 BTU of heat over the winter. Firewood costs $250 per cord, each cord contains 20,000,000 BTU, and the stove runs at 70 percent efficiency. Electricity costs $0.13 per kWh, and the electric heaters are modeled at 100 percent efficiency. These are the same values used in the page’s test notes, so they provide a good worked example.

First, calculate usable heat from one cord of wood. At 70 percent efficiency, a 20,000,000 BTU cord delivers about 14,000,000 BTU of useful heat. Dividing the 60,000,000 BTU seasonal demand by 14,000,000 BTU per cord gives about 4.29 cords. At $250 per cord, the seasonal wood cost is about $1,071.43, which rounds to roughly $1,072.

Now compare electricity. Dividing 60,000,000 BTU by 3,412 BTU per kWh gives about 17,585 kWh when efficiency is 100 percent. At $0.13 per kWh, the seasonal electric cost is about $2,286 to $2,288 depending on rounding. That means electricity costs a little more than twice as much as wood in this scenario. The break-even wood price is a bit above $530 per cord, meaning wood would have to become much more expensive before it matched the electric cost here.

This example shows why local assumptions matter. If electricity were cheaper, or if the wood were wet and the stove performed poorly, the gap would narrow. If wood were free from your own property, the wood cost would drop sharply, though your labor would still matter. If you changed the number of seasons from 1 to 5, the calculator would show the cumulative totals and make the long-term difference even easier to see.

The following table compares two usage patterns with the same prices. It illustrates how larger seasonal heat demand magnifies the dollar difference between the two heating methods when all other assumptions stay the same.

Limitations and Assumptions

This calculator is best understood as a planning tool, not a perfect forecast. It assumes that your seasonal heat demand is known and that both fuel prices remain constant over the comparison period. In reality, electricity rates can change, firewood prices can rise during cold years, and your actual heating demand may vary with weather, insulation improvements, thermostat settings, and occupancy patterns.

It also assumes that the efficiency values you enter are representative of real operation. That is a strong assumption. Wood stove performance depends on wood species, moisture content, draft, chimney condition, burn technique, and whether the stove is run in its optimal range. Electric resistance heaters are comparatively predictable, but if you are using this calculator to approximate a heat pump or another system with variable performance, the effective efficiency may change with outdoor temperature and operating conditions.

Another limitation is that the model focuses on direct energy cost only. It does not include stove purchase price, chimney installation, hearth work, maintenance, ash disposal, chimney sweeping, insurance implications, or the value of your time spent cutting, hauling, stacking, and tending wood. For some households, those non-fuel factors are minor. For others, they are central to the decision. Convenience, indoor air quality, local emissions rules, storage space, and backup power needs can all matter as much as the fuel bill.

Even with those limitations, the calculator is still useful because it answers a narrow but important question clearly: given a certain amount of heat demand, what is the estimated seasonal cost of meeting that demand with wood versus electricity? Once you have that answer, you can layer on the practical realities of your own home and lifestyle. In many cases, that is exactly the right order for making a sound decision.

Interpreting the Result

When the result appears, focus first on the total wood stove cost and total electric heater cost. Those numbers tell you which option is cheaper under your assumptions. Next, look at the break-even wood price. That figure is especially helpful because it translates the comparison into a simple threshold. If your actual delivered wood price is comfortably below the break-even value, wood has a cost advantage. If it is close, then small changes in efficiency or fuel quality could reverse the outcome.

The cumulative table is most helpful when you are thinking beyond one winter. A modest annual difference can become a large multi-season difference, while a small one-time equipment cost may be recovered quickly if the annual savings are substantial. On the other hand, if the annual savings are small, convenience and maintenance may matter more than fuel economics. The calculator does not make that judgment for you, but it gives you the numbers needed to make it yourself.

For related analyses, see the space heater vs central heating cost calculator and the patio heater electric vs propane cost calculator, both of which explore energy trade-offs in heating applications.