Everything you want to know about how Redo Energy works, how we calculate results, and what happens with your data.
Redo Energy is a collection of free calculators that help homeowners and businesses figure out whether electrification upgrades make financial sense. We cover heat pumps, solar + battery, electric vehicles, EV charging, induction cooking, and more.
Every calculator runs entirely in your browser. We use real utility rates, real climate data, and real equipment specs to give you personalized estimates for all 50 states and U.S. territories.
Yes, every calculator is completely free with no paywall, no account required, and no hidden limits. We believe everyone deserves access to good energy data.
Right now, Redo Energy is entirely donation-supported. If you find our calculators useful, you can support us on Ko-fi. Every donation goes directly toward maintaining the site, keeping our equipment databases current, and building new tools.
In the future, we plan to generate revenue through affiliate links to equipment retailers, referrals to vetted local installers, and potentially licensing our calculators to utilities, contractors, or real estate platforms. None of these will affect our recommendations — equipment scoring is purely data-driven.
No. We do not sell, share, or store your personal data. Everything runs in your browser session. See the Privacy & Data section below for details.
Redo Energy is an independent project focused on making electrification decisions easier for everyday people. We are not affiliated with any equipment manufacturer, installer, or utility company.
We use building physics modeling. From your address, square footage, and a few other inputs, we model how fast heat flows through your home's walls, roof, windows, and foundation. We then combine that with local climate data — heating and cooling patterns from weather datasets — to estimate how much energy your home needs each month.
For older homes, we also factor in the likely construction era of your neighborhood to adjust insulation quality assumptions.
The result is a physics-based estimate that's typically within 10-20% of a real energy bill for most homes, without you needing to dig up old utility statements.
We use electricity and gas rates from the U.S. Energy Information Administration (EIA) Form 861, which covers virtually every utility in the country. When you enter your address, we identify your likely utility and pull the correct residential or commercial rate.
For more complex rate structures (time-of-use, tiered, demand charges), we maintain curated rate data for major utilities. You can also override the rate manually if you know your exact cost per kWh.
Our calculators draw from many public and curated sources:
Every equipment recommendation uses multi-dimensional scoring rather than a single ranking factor. For example, heat pump scoring considers efficiency, cold-climate performance, features, warranty, and cost — weighted by your specific climate.
A home in Minnesota gets different top picks than one in Florida because we prioritize different performance characteristics based on your heating and cooling needs. The same climate-aware approach applies to solar panels, batteries, inverters, and EV chargers.
This approach means we never just recommend the most expensive product. The "Best Overall" pick balances performance, value, and suitability for your location.
Our estimates are designed to be conservative and realistic, not optimistic sales pitches. That said, every estimate involves assumptions:
We recommend treating the results as a solid starting point for decision-making, not a guaranteed dollar figure. Always get multiple contractor quotes before committing.
Different utilities charge different rates for electricity, and many have different net metering policies for solar. When you change your utility, the calculator updates your electricity rate, applicable rebates, and (for solar) the compensation structure for excess generation. All of these affect your cost and savings estimates.
We cross-reference your location, household income, and the type of upgrade against federal, state, and utility incentive databases. Federal tax credits (like the 25C energy efficiency credit) apply nationwide with specific eligibility rules. State and utility rebates are matched based on your address and selected utility.
For income-dependent programs like the IRA's enhanced rebates, we use published income thresholds (area median income, federal poverty level, etc.) adjusted for your household size to estimate your eligibility tier.
Several major incentive programs are income-dependent. The IRA's Home Electrification Rebate program (HOMES Act) offers significantly larger rebates for low- and moderate-income households (at or below 150% of area median income). The used EV tax credit has an income cap. We ask about income only to estimate which incentive tier you fall into — we never store or transmit this information.
No. Our incentive estimates are based on the best available information about current programs, but they are not a guarantee. Incentive programs can change, run out of funding, or have eligibility requirements we cannot fully verify from the information you provide. Always confirm specific incentive details with the administering agency, your tax professional, or your installer before making purchasing decisions.
The One Big Beautiful Bill Act (OBBB) repealed the residential clean energy credit (Section 25D) effective December 31, 2025. This means the 30% federal solar tax credit is no longer available for systems placed in service after that date. The commercial solar Investment Tax Credit (Section 48) phases to 0% for projects that begin construction after 2027.
Our solar calculator reflects these changes. If you already have a signed contract or system under construction, different transition rules may apply — consult your tax professional.
The federal new EV tax credit (Section 30D) was repealed by the OBBB Act effective September 30, 2025. After that date, no new federal tax credit is available for new electric vehicle purchases. The used EV credit (Section 25E) was also repealed effective December 31, 2025.
Our EV Finder reflects these changes. State and utility incentives for EVs may still be available depending on your location. We update incentive data regularly.
The individual calculators (like the Heat Pump Calculator or Solar Calculator) go deep on a single upgrade: detailed equipment comparisons, sizing, cost breakdowns, and payback analysis.
The Smart Home Planner looks at your whole home and recommends which upgrades to prioritize based on your goals. It considers heat pumps, solar, EV charging, induction cooking, and hot water heating together, showing a combined dashboard with total savings, payback, and CO2 reduction. Think of it as the strategic view vs. the tactical view.
You set five priority sliders (e.g., save money, low upfront cost, reduce CO2, energy independence, comfort) and the planner weights each upgrade category against your priorities. An upgrade that scores high on your top priorities gets recommended first.
Behind the scenes, it runs the same thermal modeling, rate lookups, and equipment scoring as the standalone calculators. The planner just adds a prioritization layer on top to help you decide where to start.
Your address is sent to Google Places (for autocomplete suggestions and geocoding) and OpenStreetMap's Nominatim (as a fallback) to determine your latitude, longitude, and state. Some calculators also send your coordinates to Google's Solar API to detect your roof size and shape, and to Open-Meteo for local climate data.
All of these requests go directly from your browser to those services — they do not pass through our servers. We do not log, store, or track your address. However, Google does see your address through their Places and Solar APIs, albeit without much context about who you are or what you're using it for beyond our site name. Google's use of this data is governed by their privacy policy.
No. All calculations run entirely in your browser. We do not have user accounts, databases, or server-side storage. The only data persisted is your theme preference (light/dark) and unit preference (imperial/metric), stored in your browser's localStorage — which never leaves your device.
Your address, income, square footage, and every other input exist only in your browser's memory for the duration of your session.
Yes. The Smart Home Planner and Smart Commercial Planner include a share feature that encodes your inputs into the URL using base64 encoding. When someone opens that link, the planner re-runs the calculations with your inputs. No data is stored on a server — everything is embedded in the URL itself.
Note: Base64 is an encoding format, not encryption. Anyone with the shared link can see the inputs (address, square footage, etc.) embedded in it. Only share these links with people you're comfortable seeing that information.
Individual calculators can generate PDF reports that you can save or email.
Your address determines almost everything in the calculation:
Without an address, we would have to use national averages, which could be off by 50% or more. A specific address lets us give you results that actually reflect your home.
Our database covers over 860 utilities serving the vast majority of U.S. households. If yours is not listed, the calculator will fall back to your state's average residential electricity rate from EIA data. You can always enter your actual rate manually for more accurate results — check your most recent utility bill for the cost per kWh.
The initial calculation may take a few seconds because the calculator is fetching live climate data from Open-Meteo and performing thermal modeling in your browser. This is normal, especially on the first run. Subsequent calculations with the same address are usually faster because the climate data is cached in your browser session.
If a calculator appears stuck, try refreshing the page. A slow or unstable internet connection can delay the climate and geocoding data fetches.
Yes. All calculators are fully responsive and work on phones, tablets, and desktops. The interface adapts to smaller screens, and all interactive elements (sliders, dropdowns, charts) are touch-friendly. For the best experience with detailed charts and comparison tables, a tablet or larger screen is ideal, but everything is functional on a phone.