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3 Predictions For Solar Energy in 2017


Photo by Elijah Hail

Non-hydropower renewables are estimated to grow to 9% of generation by 2018, according to the Department of Energy. So how big of a part will solar energy play in that total? The solar industry is coming off a record-breaking year, with an estimated 13.9 gigawatts (GW) of installed capacity in 2016, by both big business and private citizens.

Corporations installed nearly 1,100 MW of capacity at 2,000 different facilities across the country as of October 2016, and more than 1 million homeowners in the U.S. have chosen to install solar panels on their personal properties. Experts agree that solar power is finding its place in the U.S. energy marketplace, but what’s in store for this hot commodity in 2017? Here are some predictions for this year and what it means for solar power.

Cost of Solar Panels Will Continue to Drop

Solar panel technology has never been more affordable than it was last year, and it’s likely to continue to decline in price. The cost of manufacturing solar panels, and thus the cost to consumers, dropped by roughly 30 percent in 2016 and is even expected to become the cheapest form of new electricity for 2017. This will make solar energy a much more compelling and viable investment for all types of households. As the market become more competitive, homeowners can benefit even more by taking advantage of the best deals. By comparing several systems and installers at once with services like 123SolarPower, the homeowner gets the most suitable offer possible.

The decline in cost also applies to the corporate solar market. “Unsubsidized solar is beginning to out-compete coal and natural gas on a larger scale, and notably, new solar projects in emerging markets are costing less to build than wind projects,” according to data from Bloomberg New Energy Finance. In the last decade solar installations have grown by 60 percent per year while the cost has fallen by more than 70 percent, says SEIA.

More Technologically Advanced Solar Panels

As with most new technologies, the look and functionality of solar panels continue to develop. Some of the latest types of panels look nothing like the original crystalline silicon cells strapped to people’s roofs. A new product launch by Sunflare brought us “sticky and flexible” solar panels. This new type of panel can be placed onto walls and roofs and does not use glass substrate like traditional panels. The company also boasts that the panel is more environmentally friendly, because it requires less energy to manufacture.

New panels are not only more functional but are also designed to be aesthetically pleasing. Due to criticism for the way solar panels look on top of homes, their appearance has undergone quite a makeover and will likely continue to change in 2017. For example, several manufactures are producing frameless solar modules to streamline the look, and last year, Tesla’s new roof panels blew innovation out of the water with its shingle designs that are practically indistinguishable from a traditional roof. This expansion of solar panel styles will be an additional benefit for homeowners who are looking for a smart investment that will also increase their property value.

Solar Energy Storage Will Become More Affordable

Experts predict that energy storage will become more affordable in 2017. The accessibility to storage devices is a critical piece of the puzzle for widespread renewable energy adoption. The technology of choice thus far has been battery energy storage, lithium-ion batteries to be exact. These types of batteries saw significant price declines in 2016 and can be used in a variety of applications, all of which will help foster solar power adoption this year. Similarly to the solar panels themselves, pricing is a major element in the position of energy storage.

The good news is, a report from Deutsche Bank projects the cost of lithium-ion batteries could fall by 20 to 30 percent a year, bringing commercial or utility-scale batteries to the point of mass adoption before 2020. The energy storage market is forecast to exceed the 2-gigawatt mark in 2021 and valued at almost $3 billion, reports GTM Research.

Several states have introduced policies and programs to support energy storage technology markets with the intent to promote emerging technologies. In 2010, California signed Bill 2514 into law, which adopted a 1.325 GW procurement target for electricity storage by 2020, with targets increasing every two years from 2016 to 2020. States like Florida, which have high exposure to natural disasters, are also recognizing the role that energy storage can play in disaster planning. 115 emergency shelters in the state have installed PV systems with battery storage, which will most likely continue to spread.

The coming year should prove to be another record-breaking one for solar power with the advancement of technologies, making it more affordable and accessible for both commercial and residential uses. If you’d like to see how much it would cost to install solar panels on your home, visit a solar panel marketplace.

Sarah Kezer is passionate about helping others take advantage of the power of solar energy. At 123SolarPower, Sarah assists in answering questions and providing expert information for users to explore their options when it comes to going solar. 123SolarPower connects individuals with the largest network of solar power providers in the U.S. Connect with Sarah on Twitter and Facebook, and read all of her MOTHER EARTH NEWS posts here. 

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

Learn How Solar Rebates and Incentives Can Reduce Your Installation Costs

home solar panels

A home solar energy system is one of the best ways to reduce your carbon footprint, increase your home value, and lower your electricity costs for decades to come. In recognition of the many benefits that solar offers for homeowners and the environment, many organizations – including the federal government, states and towns, and electric utilities – have established incentive and rebate programs to lower the cost of solar. Income tax credits, rebates, and tax exemptions are just a few of the incentives that could be available where you live.

State and Federal Income Tax Credits are a Significant Incentive

If you’ve spent any time researching solar, you probably know about the federal investment tax credit for solar. This nationwide incentive, which was recently extended through 2019, allows homeowners to deduct 30 percent of the gross cost of installing solar from their federal income tax. In effect, that means a 30 percent savings off of the list price. 

What you may not know, however, is that some states also offer income tax credits for solar. The state solar tax credit is one of Arizona's best solar incentives, and a diverse set of other states across the country, including New York, Oregon, South Carolina and Utah have similar programs.

Your Local Utility May Offer Rebates

Even if your state doesn’t have a tax credit, you may be able to get cash back on your solar investment with rebates through your electric utility. Many local and municipal utilities across the country, including two of the country’s biggest states for solar, California and Texas, offer solar rebate programs to their ratepayers.

Some of the utility solar rebates in California can reduce your solar costs by 25% or more. Silicon Valley Power’s rebate program, for example, currently offers a $1.25/watt rebate. Just how significant is a $1.25/watt rebate? EnergySage Solar Marketplace customers in California paid an average of $3.62/watt for their solar PV system, which means that a $1.25/watt rebate can cut their solar costs by more than a third.

In Texas, solar rebate programs from utilities are one of the Lone Star State’s biggest solar incentives. Austin Energy, CPS Energy, and other municipal utilities and electric cooperatives will provide rebates if their customers install solar on their homes and businesses.

Sales Tax and Property Tax Exemptions Offer an Additional Savings Opportunity

In addition to its environmental benefits, solar energy is a great way to increase your home's value by tens of thousands of dollars. However, higher property values come with a higher property tax bill. To combat this issue, many states have enacted legislation that prevents solar from being included in appraisals for property taxes. In addition, solar energy equipment is often exempt from sales tax, which can be a significant cost saver in states with high sales tax rates. Tax exemptions are one of the main incentives for solar in Florida

Certain States Have SREC Programs That Can Put Extra Cash in your Pocket

Tax credits, rebates, and tax exemptions are three of the most popular policies that states and local governments use to encourage the adoption of solar. However, a few select states take it a step further – solar system owners can actually make money by selling the solar renewable energy certificates (SRECs) associated with the electricity their panels produce. SRECs are one of the main New Jersey solar rebates and incentives, and can help you save thousands of dollars over the lifetime of your solar panels.

Use a Custom Solar Calculator to Find Out What Solar Will Cost for You

If you’re curious about how much you can save with the financial incentives for solar that are available in your area, use the custom solar calculator at EnergySage. This one-of-a-kind calculator incorporates local utility electricity rates, available incentives, and price data from the EnergySage Solar Marketplace to give you a customized estimate of your 20-year solar savings.

Vikram Aggarwal is the founder and chief executive of EnergySage, the online solar marketplace. EnergySage simplifies the process of researching and shopping for solar. By offering shoppers more choices and unprecedented levels of transparency, EnergySage allows consumers to select the solar installation quote that provides the best value for them, quickly and easily. Read all of Vikram's posts here.

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

Solar On Its Way to Being Cheapest Power Source Everywhere


Photo by Upsplash

Solar energy has been making serious gains in recent years. Increased awareness of the environmental effect of fossil fuels, improvements in solar technology, rising investments and more widespread adoption have all led to a drop in the price of solar energy. Now for the first time, solar is en route to becoming the cheapest source of power available.

More Countries Using Solar

According to a report by the World Economic Forum (WEF), solar energy is now cheaper than or the same price as fossil fuels in more than 30 countries. WEF also estimated that, within only a few years, two-thirds of countries will reach the same point.

In 2016, the U.S. added about 9.5 gigawatts (GW) of solar power to the grid, making solar the biggest source of added capacity that year. The year 2016 was the first that solar became the power source with the most additions. The number is even higher — 11.2 GW — when including solar installed for homes and businesses, as opposed to only utilities. Countries around the world from Chile to Saudi Arabia to China are adding solar capacity at record paces and energy companies are bidding on solar contracts in auctions at unprecedented lows.

Solar Prices Falling

Ten years ago, generating solar energy cost about $600 per megawatt-hour (MWh) compared to around $100 for coal and natural gas. Today, solar costs about $100 per MWh. The price is expected to keep dropping. By 2025, solar will likely be cheaper than coal across the globe. Solar may be getting cheaper for a number of reasons.

Improvements in technology have made energy from the sun much cheaper to produce. Today, less than half of solar costs come from producing the actual materials, meaning that most of the expenses come from things like installation and connecting to the grid.

Improvements in energy infrastructure, such as installation of smart grids, will likely help make solar more attractive too. An increase in the amount of investment in the solar industry, government subsidies and increased awareness of climate issues are also leading to solar’s increasing popularity.

Effect on Oil and Gas Industries

An unprecedented 16 oil and gas companies went bankrupt this past year, according to a study by accountancy firm Moore Stephens. The report found that this was due to a drop in oil prices from $120 to $50 a barrel, a change many smaller companies were unable to deal with.

The drop is likely due to decreased demand for oil as more consumers are getting their power from renewables. French energy company Engie believes the price may keep falling and even drop to as low as $10.

Looking Forward

Of course, fossil fuels are not entirely out of the picture, but the changes bring to light a shift in the energy industry. Renewable energy has become economically viable, even lucrative, and the industry is taking advantage of that development. Many major energy companies that have been in the fossil fuel for years are now investing in renewables, selling off coal plants and decommissioning nuclear facilities.

It’s could be quite beneficial for companies that have long worked with fossil fuel companies to start collaborating with renewable energy producers as well. For example, the strategic use of fabricated metals for safety issues on oil and gas drilling sites led to a large market for those materials in the fossil fuel industry. Manufacturers could tap into a similar market in the renewables sector. Some are calling on governments, as well, to offer help to workers displaced by a shift toward renewable energy.

Despite all of this growth, investments may not yet be high enough to stop negative effects from climate change. The Paris climate change accord set a goal of $1 trillion for global investments in renewables. Investment today is at 25 percent of that goal.

The research says that solar will likely continue on its way to becoming the world’s cheapest source of energy. How exactly that will affect the economy, the environment and workers remains to be seen.

Kayla Matthews writes and blogs about healthy living and has an especially strong passion for helping others increase their mental health and happiness by improving their daily productivity and positivity. To learn more about Kayla, you can follow her on Google+Facebook and Twitter and check out her most recent posts on Productivity Theory. Read all of her MOTHER EARTH NEWS posts here.

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

How to Profitably go Solar in 2017: Tips from Hawaii


What comes to mind when you think about Hawaii? It’s likely a combination of ocean waves, palm trees, blue skies and sun. If your mind also moves in the direction of abundant solar energy, you wouldn’t be wrong. Hawaii’s climate and location makes the island a perfect place to collect and apply solar energy. Given this environment, plus high costs of electricity generated by imported fuels facing all island communities — which soar to rates of up to 37.6 cents per kWh — it’s clear why individuals in Hawaii are highly interested in alternative energy options. It’s something literally and figuratively in their nature — Hawaiians share an ethic of independence, one that extends to not being dependent on the grid.

However, in order to reduce fossil fuel reliance and gain energy independence, consumers in the Hawaiian market need to adhere to utility regulations in order to ensure alternative energy use remains profitable. Below are three tips solar users around the world can take from Hawaii’s push to profitably leverage solar energy.

Know the Regulations — and Restrictions — Surrounding Alternative Energy in Your Area

Last year, the Hawaiian Electric Company eliminated net energy metering (NEM) and pushed to instill an interconnection policy that would create certain roadblocks on the journey to grid-connected solar energy. As a result, solar energy risked appearing to be more trouble than it was worth for new investors, despite Hawaii leading the nation for solar penetration rates. In any location, it’s critical for solar users to remain aware of local legislation surrounding alternative energy use, as well as any solutions that can help overcome obstacles.

For example, intelligent inverters and energy storage can help Hawaiian residents — and others around the globe in similar situations — to increase solar power value, avoid the grid’s common problems and reap the benefits of self-generation. Since certain batteries no longer require frequent maintenance or replacement, users can store solar energy during peak hours and apply that power after the sun goes down. With this in mind, the recent HECO changes have resulted in encouraging electricity consumers to consider adding energy storage to realize the best economic payback for their solar investment.

Utility Companies and Consumers Should be Ready to Adapt

When choosing alternative energy sources, consumers are first and foremost interested in reliable, consistent power at economic prices. This intersects with a utility company’s perspective, which sees the entire industry’s delivery dynamics changing.

Previously, utility companies’ revenue came from investments in physical infrastructure — literally putting more steel in the ground. Solar energy decreases the need for such infrastructure while decreasing load growth. In response, utilities are learning new ways to adapt, such as instating metering charges, monthly minimum bills and additional fees. To find a sustainable compromise, utility organizations and consumers should be flexible and prepared to adapt to new systems of energy measurement and billing.

Remember that Energy Independence is Possible with the Right Tools

Alternative and renewable energy is attractive for residents and business owners in cities and rural areas around the globe. It doesn’t matter if an area is rich in solar resources, such as the case in Hawaii, or if most days bring rain instead of sun, such as in Seattle — reducing dependence on fossil fuels and the grid can be a compelling prospect. It’s also a viable option with the use of solutions such as intelligent inverters combined with energy storage.

Consumers should also remember that the best option usually involves teaming up with the grid and not sever relations with it. In many cases, a happy medium, made possible by modern technology, can offer increased independence and improved performance without the hassle of attempting off-grid energy management.

For example, intelligent inverters can charge and maintain batteries while managing grid use, keeping users off the grid for long periods of time and drawing from its resources in order to meet spikes in demand. This process, called “zeroing out,” is a solution to achieving greater independence without the inconvenience of going off the grid. Utility companies remain open to working with consumers to help them achieve their energy goals, and new solar and storage technology is there to help both sides.

Photo by Pixabay/Blickpixel

Eric Hill is senior strategic platforms manager at Alpha Technologies, parent company of OutBack Power. He has 8 years’ experience in energy storage focusing on renewable energy, telecom, wireless, industrial utilities, and broadband cable TV. Connect him on LinkedIn, and find OutBack Power on Twitter and Facebook. Read all of his MOTHER EARTH NEWS posts here.

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

Can’t Put Solar on Your Roof? Consider One of These Creative Uses


Photo by Jon Styer/Eastern Mennonite University

Homeowners across the United States are reducing their electricity costs and their carbon footprints by installing solar. For many solar shoppers, rooftop systems are the best home solar option. However, not every home has a roof that’s suitable for solar. Certain roof types, like slate and cedar tiles, are too fragile for solar panels. If trees shade your roof, you’ll have less-than-ideal solar electricity production, and some homeowners' associations and historical associations have rules that restrict solar panel installations. 

Luckily, there are a variety of alternative solar options for every situation. Whatever the reason is that you can’t install rooftop solar, there’s a solution available that can suit your needs.

Solar Sheds, Barns, and Carports: Use Alternative Roof Space to Host Your Installation

The roof is the most common place for a home solar installation, and for good reason. Your roof is elevated, so it’s typically exposed to the sun for most of the day. It’s also an existing structure, which can reduce your installation costs. Many homeowners who can’t install panels on the roof of their home will build a solar energy system on another building on their property. Sheds, garages, greenhouses and barns can all offer suitable locations for solar installations.

Solar carports and patio covers are another increasingly popular rooftop solar alternative. If you construct a carport or patio cover, you have an installation that both generates zero-emissions electricity and provides shade. As an added bonus, both options can be installed so that they capture sunlight at the perfect angle to maximize your solar energy production.

Ground Mounted Solar Systems: All the Benefits of Rooftop Solar, With Less Maintenance

Even if you don’t have any roof space that can host a solar energy system, you still have options for home solar. Ground mount solar panels offer all of the benefits of a rooftop system, plus a few additional advantages. In many cases, a ground mount system will actually produce more electricity than rooftop solar, because it can be adjusted to capture more sunlight throughout the year as the sun’s position changes in the sky. Additionally, while a rooftop solar system will be restricted by the size of your roof, a ground-mounted system can be sized to meet your exact needs.

If your homeowner’s association has rules against solar panels for aesthetic reasons, or if you live in a historic neighborhood, ground mount solar panels can offer a good solution. In most cases they don’t violate aesthetic regulations as long as you install them so that they can’t be seen from the street.

Community Solar: Own a Share of a “Solar Garden” in Your Area

If you can’t install solar panels anywhere on your property — or if you don’t own your home — there’s an option for you, too. Community solar, often referred to as “shared solar” or “solar gardens,” is a way for you to use solar energy even if you can’t build a system at your property.

Your community solar options will depend on where you live. In many cases, you can either “subscribe” to a solar garden or own a share. If you subscribe, you pay a monthly fee in exchange for a portion of the solar electricity from the array. If you own a share, you pay up front (similar to buying a rooftop system) and receive the solar electricity from your share for the lifetime of the system.

Community solar is a good option for everyone, but it’s a particularly helpful solution if you’re a renter, you plan on moving in the near future, or if your property isn’t suitable for a solar installation.

Compare All of Your Solar Options Before Making a Final Decision

Each rooftop solar alternative offers distinct advantages, and some rooftop solar alternatives cost more than others. Regardless of which type of installation you choose, we always recommend comparing all of your options before you make your final decision.

If you’re interested in shared solar, use a database of community solar projects to find all of the options available near you. For carports, ground mount solar, and other rooftop solar alternatives at your property, you can receive quotes from qualified solar installers in your area by joining the EnergySage Solar Marketplace — just specify what type of installation you’re looking for when you sign up.

Vikram Aggarwal is the founder and chief executive of EnergySage, the online solar marketplace. EnergySage simplifies the process of researching and shopping for solar. By offering shoppers more choices and unprecedented levels of transparency, EnergySage allows consumers to select the solar installation quote that provides the best value for them, quickly and easily. Read all of Vikram's posts here.

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

Grid-Tied vs. Off-Grid Solar: Which is Right for You?


Solar offers more than just an opportunity to reduce your carbon footprint. When you install solar panels on your roof, you are a step closer to taking your electricity production and consumption into your own hands. One of the biggest decisions solar shoppers have to make is whether to install a standard grid-tied solar energy system, a solar battery backup, or a fully off-grid solar energy system. Here’s everything that you should keep in mind when you’re deciding between grid-tied solar vs. an off-grid solar battery backup system.

Why Many Homeowners Choose a Grid-Tied Solar System

Off-grid solar technology is becoming more advanced every year, and a growing number of companies are manufacturing solar batteries for home. If you install battery storage along with your PV system, you can store excess solar electricity when it’s produced and then use it as needed later. Theoretically, this means that you can completely sever your connection with your electricity utility. In practice, it often makes more sense to stay grid-tied, particularly if you live in an area with significant climate variation.

Most of the solar batteries for home use available today, like the Tesla Powerwall, are designed to store solar energy generated during the day for your home to use at night. This can help you reduce your reliance on utility electricity by storing your excess solar power at home instead of feeding it back into the grid. 

The trickier proposition is generating and storing enough extra solar electricity in the summer when solar power generation is highest to cover your future needs in the winter, when solar potential is at its lowest. According to EnergySage Marketplace data, the average solar shopper offsets 86 percent of their annual electricity use with solar – a significant amount, but not enough to go fully “off the grid.”

Preventing total power loss in the event of a winter snowstorm or an extended period of overcast days would require a lot of storage capacity, a very large solar panel system, and a significant financial investment to install. While it is technically feasible to go off the grid with solar batteries, it’s rarely cost effective when compared to the benefits of staying grid-tied. 

Can You go Off-Grid With Your Solar Panels?

Grid-tie solar is the best option for many homeowners, but there are plenty of situations where taking your home off the grid with a solar battery backup makes sense.  In some places, particularly in remote areas, off-grid solar battery systems are the best (or even the only) option. There are a few criteria your property should meet to be a good fit for off-grid solar.

First and foremost, you need to have very low electricity demand. If you construct a net zero energy home or conduct major home energy efficiency retrofits on your existing home, powering your property with off-grid solar-plus-storage can be a feasible option. You also need to have the financial capacity to invest in a solar battery backup, which will add thousands of dollars to your solar installation.

Even if you don’t take your home fully off-grid with a solar battery backup, there are still opportunities for you to use solar-plus-storage technology. Many do it yourself solar options with batteries are available if you want to install solar-powered lighting or electrify outlying buildings on your property, like barns and tool sheds. Tiny houses, boats, and RVs are also great candidates for solar-plus-storage – they have comparatively small electricity needs and are already designed for “off grid” use. 

Using Solar Battery Backup with a Grid-Tied Solar-Energy System

For the average solar homeowner in the United States, it usually makes sense to maintain a connection to the utility company. However, even if you don’t choose to go fully off-grid, you can still install a solar battery backup with your PV system.

Solar-plus-storage systems that include a battery are particularly beneficial if your utility doesn’t have a good policy for compensating homeowners who generate excess solar electricity. For example, some utilities don’t have retail rate net metering for solar, which means you won’t receive a full bill credit for solar electricity that you send back to the grid.

If you live in California, net metering 2.0 means that new solar homeowners will be enrolled in time-of-use rates with their utility. As a result, the credit you receive for your solar electricity will vary depending on the time of day – electricity sent back to the grid during peak hours generally results in higher value credits. In both of these cases, you can benefit from storing your excess solar energy at home even though you’re still connected to the grid.

In addition to making it easier for you to manage your solar electricity generation and use at home, solar batteries can provide a few hours of backup power in the event of a power outage. If you’re already installing a solar PV system, including a battery can be more cost-effective in the long term than a diesel-powered backup generator.

While most homeowners can’t go completely off the grid with a solar battery backup, solar panels are still a strong investment, and storage technologies are becoming cheaper every year. Even if you don’t invest in energy storage now, you can ask your solar installer to make your system “storage ready” so that, a few years down the line, you can easily install a solar battery backup. Use the EnergySage Solar Marketplace to get multiple quotes from pre-vetted local solar installers and find the right solar-plus-storage option for your home.

Vikram Aggarwal is the founder and chief executive of EnergySage, the online solar marketplace. EnergySage simplifies the process of researching and shopping for solar. By offering shoppers more choices and unprecedented levels of transparency, EnergySage allows consumers to select the solar installation quote that provides the best value for them, quickly and easily. Read all of Vikram's posts here. 

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.

Dual-Mode Hot-Water System Heated with Solar and Wood

How the Dual-Mode Solar-and-Wood Water Heater Works

Having hot water for showers and dish washing is certainly a joy that makes off-grid feel as luxurious as on-grid, yet without utility bills or fossil fuels. Where I live, summer sunshine is abundant, but winter cold requires the heat of a woodstove.

In summer, I connect to the solar hot water panel in the greenhouse, and in winter to the hot water coil on the wood stove pipe. I have cold and hot water tanks, located upstairs, to provide gravity-fed hot and cold water to a kitchen sink and a shower on the lower floors. The hot water tank is filled manually, by a pipe and valve plumbed from the cold tank.

I let the hot water tank heat all the water in the tank to a usable temperature and then use it. Hot water is circulated to the hot water tank by heat convection — no pumps.


The solar collector heats my ten gallon hot water tank to 120 degrees Fahrenheit in about three hours on a summer day, even if partly cloudy — the stove pipe coil heats the tank above 130 degrees F in about two hours, or three hours if the starting temperature of the tank is near ice-cold.

A surprising discovery is that the hot water coil will lower the stove pipe temperature by 100 degrees F when water is circulating. Depending on how hot the water in the tank is, and if I mix cold at the faucet, showers use 2-1/2 gallons and washing dishes use 2 to 4 gallons per day. The tank will drop about 20 degrees F overnight or after the woodstove has stopped burning.

Solar Hot Water Collector

The solar hot water collector panel is made with an array of CPVC pipe on a flat plate collector (3 feet by 5 feet). It has ten 1/2-inch collector tubes that “T” into a top and bottom manifold that is 1 inch CPVC and routes to the hot water tank. CPVC pipe can withstand 200 degrees F, while the hottest temperature on my flat-plate collector is 130 degrees Fahrenheit.

solar hot water panel

Stove Pipe Hot Water Coil

The hot water coil is 3/8-inch copper tube that is coiled around the stove pipe about a dozen times and joins 1-inch copper pipe that is routed to the hot water tank. Copper pipe can withstand boiling water without damage. Do not use plastic fittings with copper pipe because plastic will melt. The stove pipe can get very hot, over 500 degrees F, and it could easily turn the water in the hot water coil to steam in a closed system, unless you have an open tank with a loose-fitting lid so that no steam pressure will build up.

hot water coil

Summer and Winter Modes

When the season changes, I simply swap the connection to the hot water tank between the pair of CPVC pipes from solar for summer, to the pair of copper pipes from the woodstove for winter.

summer-winter pipes

Heat Convection Loop and Hot Water Tank

Two key points to remember about using heat convection to circulate hot water from the heat source to the hot water tank:

1) Heat convection flow will stall if there is too much resistance. That means the pipes must be large diameter, 1-inch minimum, and routing must have gentle angles — never use a 90 degree turn, instead use two 45-degree fittings or a flexible hose (the metal type used on typical hot water tanks). Heat convection flow will stop if the tank water level drops below the hot water inlet.

2) Heat convection requires that the heat source (where the heat is collected) be lower than the hot water tank (where the heat is stored). The tank should have four ports, one is the fill inlet and one is the hot outlet, and two for heat convection. The hot water inlet port that brings hot water from the heat source must be ABOVE the hot water return port.

Similarly, hot water output is from the TOP of the solar collector and/or the hot water coil, while the cold water return is supplied to the BOTTOM of the solar collector and/or the hot water coil.

hot water tank

More ideas for your homestead and small house are in Christopher James Marshall’s holistic guide, Hut-Topia: How to Create Sustainable Small Homes and Homesteads. Read all of his MOTHER EARTH NEWS posts here.

All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Guidelines, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on their byline link at the top of the page.