Zero Energy Ready Homes can generate electricity at home to slash utility bills
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As net zero energy homes become more mainstream, homeowners are looking for ways to generate electricity at home.
In fact, about half the U.S. single family housing market is close to meeting the U.S. Department of Energy's Zero Energy Ready Home criteria.
What is a DOE Zero Energy Ready Home?
It’s a home that meets all of the criteria found in the DOE Zero Energy Ready Home Requirements. These homes are verified by a qualified third-party and are at least 40 percent to 50 percent more energy efficient than a typical new home. This generally corresponds to a Home Energy Rating System (HERS) Index Score in the low to mid-50s, depending on the size of the home and region in which it is built.
By 2013, nearly 220,000 homes were rated with an average HERS Index Score of 64. Assuming a basic bell distribution curve, that means upwards of a 100,000 homes last year achieved HERS Index Scores on or the Zero Energy Ready performance threshold from low to high 50’s, said Sam Rashkin, chief architect, Building Technologies Office for the Department of Energy.
The homes are built with the goal of moving toward zero net energy use with the use of renewable energy along with reduced energy demand from high performance building techniques. That means the home's energy demands are low enough to be reasonably offset by renewable energy. The home produces energy that's fed back into the electrical grid to offset the home's energy use over the course of a year.
Once you have a Zero Energy Ready Home, how do you get to zero energy costs?
Here's a review of the three main types of renewable energy sources in the U.S. today.
Solar power for homes
Until now, homeowners had three choices for solar power: buy the panels and system outright; engage in a lease; or use a power purchase agreement.
Now there's a fourth way: solar sharing.
Yeloha Inc. launched The Solar Sharing Network, a platform designed to remove the obstacles that going solar once presented (including needing your own roof!) in order to unleash the economic and environmental benefits of solar energy to everyone, regardless of where a person lives.
With Yeloha, residents who live in apartments, rent their homes, have shaded roofs, or don’t wish to install panels can easily purchase energy generated on someone else's roof. They can expect to save 10-50% of their electric costs by joining Yeloha compared to what they are currently paying for their electricity. Joining is a simple online experience, and savings are directly applied to customers’ current electric bill.
Utilizing the peer-to-peer shared economy model, the Yeloha team is determined to change the profile of a solar user from a single homeowner who only benefits themselves, to one of a “Sun Host” who helps unleash the benefits of going solar not only for themselves but also for others who have never had access to solar before - “Sun Partners.”
Yeloha’s Solar Sharing Network opens the solar market to customers who rent their properties and/or live in an apartment building as well as those whose roofs are physically unsuitable for solar. For these individuals, Solar Sharing offers a new way to buy into solar from a separate locale. Now, everyone with an electricity bill, no matter where they live, can have the opportunity to go solar and save.
How does Solar Sharing work?
Energy makers: In exchange for hosting, property owners become “Sun Hosts” by receiving solar panels, installation, and a portion of the energy generated, all free of charge. Similar to the way Airbnb Hosts put their extra room to work, Yeloha’s Sun Hosts put their roof to work for both personal gain and making a positive impact.
Going solar on someone else’s roof: Residents who live in apartments, rent, have shaded roofs, or don’t wish to install panels can now become “Sun Partners” and purchase online solar energy generated on their Sun Host’s roof.
The savings appear directly on both sides’ monthly electricity bills. It’s simple, with no need for expensive solar installations or even navigating away from their existing utility. That clean energy will be cheaper and cleaner than the electricity they currently buy from their local utility.
If you have a typical solar photovoltaic energy system on your home, it can add about $15,000 to the value of a home, according to a new study from the Lawrence Berkley Laboratory.
A multi-institutional research team of scientists led by the U.S. Department of Energy’s Lawrence Berkley Laboratory (Berkeley Lab), in partnership with Sandia National Laboratories, universities, and appraisers found that home buyers consistently have been willing to pay more for homes with host-owned solar photovoltaic (PV) energy systems —averaging about $4 per watt of PV installed—across various states, housing and PV markets, and home types. This equates to a premium of about $15,000 for a typical PV system.
The team analyzed almost 22,000 sales of homes, almost 4,000 of which contained PV systems in eight states from 1999 to 2013—producing the most authoritative estimates to date of price premiums for U.S. homes with PV systems.
“Previous studies on PV home premiums have been limited in size and scope,” said Ben Hoen, the lead author of the new report. “We more than doubled the number of PV home sales analyzed, examined a number of states outside of California, and captured the market during the recent housing boom, bust, and recovery.”
More than half a million U.S. homes had PV as of 2014, and the number is growing rapidly. The growth in home PV systems means that the real estate industry will need reliable methods to value these homes appropriately. Further, having greater certainty in those methods will likely facilitate additional growth in the residential PV market.
“As PV systems become more and more common on U.S. homes, it will be increasingly important to value them accurately, using a variety of methods,” says co-author Sandra Adomatis, an appraiser who helped develop the Appraisal Institute’s Green Addendum and who has written and spoken extensively on valuing green features. She noted, “Our findings should provide greater confidence that PV adds a quantifiable premium to a wide variety of homes in California and beyond.”
Wind power for homes
While solar power grabs more headlines, wind power remains a popular way to generate electricity at home. And there may be more land with suitable winds than previously thought.
New wind resource maps are showing the ability for advanced wind turbines to reach stronger winds higher above the ground, unlocking a previously untapped wind resource area that the U.S. Department of Energy says could eventually bring wind energy development to every state in America, according to the American Wind Energy Association.
New wind turbine designs are putting one of the largest domestic energy resources to use – the strong, consistent winds that can be found high above the ground in nearly all parts of the United States.
Small wind turbine equipment and installations qualify for a 30 percent federal tax credit through 2016. Businesses and agricultural institutions can receive additional federal incentives such as accelerated depreciation, USDA grants and guaranteed loans. Click here for more details on federal incentives. State level programs can make owning a wind turbine surprisingly affordable. Click here to see if your state offers additional incentives.
"Wind generation has more than tripled in the United States in just six years, exceeding 4.5 percent of total generation, and we are focused on expanding its clean power potential to every state in the country," said Energy Secretary Ernest Moniz. "By producing the next generation of larger and more efficient wind turbines, we can create thousands of new jobs and reduce greenhouse gas emissions, as we fully unlock wind power as a critical national resource."
“Wind turbine technology has advanced in just a few decades from the Model T era to more like that of a Tesla Model S," said AWEA CEO Tom Kiernan. "Advanced towers, blades and improved electronics to operate and maintain the turbines are all part of this revolution.
“The technological advances described by Secretary Moniz have redrawn the wind resource map, validating the opportunity for all states to host wind development. Our domestic wind resource is massive – enough to meet our electricity needs 10 times over – but largely untapped,” added Kiernan.
More than 1,000 American wind turbines are already accessing higher wind resources with towers reaching 100 meters or more above the ground, rather than the 80 meter standard that had been the state-of-the-art for multiple years. Heights up to 120 meters or more are already common in Europe, allowing the stronger, steadier winds at that elevation to be tapped. At 110-meter hub heights, DOE expects the land area with physical potential for wind deployment in the U.S. to increase 54 percent and at 140-meter hub heights, the potential land area would increase 67 percent.
Advancement in turbine technology, including raising hub heights to 140 meters and lowering specific power, would open up an additional one-fifth of the land area of the United States for wind turbine locations, lighting up many parts of the country, especially the Southeast U.S.
AWEA reported the U.S. wind industry completed 131 megawatts of generating capacity in the first quarter (traditionally the slowest quarter of the year for completions). These wind turbines were installed across three projects in different states with most of the new capacity installed in Texas (110 MW), followed by Iowa (20 MW) and New York (1 MW).
Wind developers also reported 1,200 MW of new construction activity in the first quarter of 2015 for projects that were previously under development, contributing to more than 13,600 MW of total capacity under construction as of March 31.
The top state with the most under construction is Texas, where a “wind rush” is underway with more than 7,800 MW being built, most of it connected to the Competitive Renewable Energy Zone (CREZ) transmission lines in West Texas. Rounding out the top five are Oklahoma with over 890 MW under construction, Kansas with more than 870 MW, New Mexico with 680 MW, and North Dakota with over 530 MW.
Geothermal heating and cooling
Geothermal heating and cooling has taken its place as a renewable energy source for the home. While it doesn't generate electricity, geothermal or ground source heat pumps are among the most energy efficient home heating and cooling options available.
Instead of using fossil fuels for heating, or electricity for cooling, geothermal systems take advantage of the steady temperatures under the ground. The ground loop pipes exchange heat with the ground, heating or cooling the home as needed. The systems use electricity only for the heat pump unit and fans to distribute the air. These minimal electric use can be offset by solar or wind power.
Geothermal systems are eligible for 30 percent federal tax credits through the end of 2016. This is in part to offset the cost of installation for the ground loops.
Real estate developers are looking at geothermal ground loop systems from the community point of view, rather than for individual homes.
Advanced Energy Capital, LLC (AEC), an energy finance company, partnered with EarthPoint Solutions to finance up to $25 million in geothermal loop installations in North America.
"The geothermal industry has been plagued by barriers the most significant being financial. We believe this new model will not only break down the barriers but allow geothermal to be on par with conventional heating and cooling options," said Tim Weber, Director of Sales at EarthPoint.
The first group of transactions – geothermal loop installations on new construction for commercial and multi-family real estate projects – are expected to fund in the Fall of 2014 and early 2015. EarthPoint’s focus is to save real estate project developer’s money and help them lower their building’s carbon emission footprint.
Bosch Thermotechnology and Orca Energy teamed up to to jointly market a geothermal ground heat exchanger and equipment solution to developers, home builders, and new home buyers in the United States.
The agreement to collaborate in the U.S. marketplace is intended to solve one of the most persistent challenges facing the geothermal industry: how to overcome builder and homeowner resistance to the initial capital cost of installing the ground heat exchanger. According to the companies, geothermal heat pump systems can save between 30-50 percent in heating and cooling costs. First costs for installing the geothermal ground loop, however, have been a stumbling block the industry has struggled with for years.
Homebuilders who enter into agreements with Orca Energy will receive design, installation, and maintenance services for the ground heat exchanger at no expense. Orca Energy will serve the homeowner as a separate utility provider for the thermal energy provided by the geothermal heat pump system. Under such master agreements, the builder agrees to have Bosch geothermal heat pumps, manufactured by Bosch’s FHP Manufacturing division in Fort Lauderdale, Fla., installed in the new homes.
Orca Energy will charge the homeowner a one-time connection fee and then bill a monthly utility charge (MUC) consisting of a capacity charge and a variable monthly energy charge. These charges are indexed to the consumer price index (CPI). The MUC is designed to be set at or below actual space heating and cooling and hot water energy costs as compared to a conventional HVAC system. This provides the homeowner with stable and predictable energy costs over time.
The push for utilization of geothermal is moving ahead. A new mixed-use planned community in Austin, Texas, aims to have 7,500 homes built to net-zero standards.
Bosch partnered with Taurus Investment Holdings, a Boston-based real estate development company, to equip a new 7,500 home master-planned net zero community outside Austin, Texas, with geothermal heat pumps, hot water systems, and Energy Star appliances.
The new community, called Whisper Valley, will eventually include some 7,500 net zero ready single and multi-family homes and apartments, plus 2+ million square feet of retail and office space across 2,062 acres. All structures will be geothermal and solar equipped, capable of achieving the net zero energy, or carbon neutral, standard adopted by the city of Austin’s municipal building code for all new construction homes. The project is said to be one of the 10 biggest developments of its kind in the United States.
Bosch, along with other manufacturing partners BASF, Rehau, Lighting Science Group Corp., and Aten Solar, are part of Taurus’ EcoSmart Solution LP (ESS) subsidiary, which develops alternative energy structure programs in large-scale real estate projects. The ESS network includes technology, construction, communications, and finance companies, among others.
Bosch said the ESS solution is being applied to Whisper Valley to meet a growing demand by homebuyers who seek to lock in lower costs for energy by employing geothermal technology for heating and cooling their home together with solar energy generation. Combining geothermal with solar is one of the most effective ways to achieve a net zero energy home.
Whisper Valley homeowners will incur no upfront costs for the geothermal system, as the ground loop infrastructure is pre-installed throughout the community. Homeowners will receive an extended warranty and no maintenance costs for the first three years. Their energy costs will be fixed at approximately $175 a month, which covers the costs of the geothermal infrastructure equipment, a solar PV system, LED-lighting package, appliances, and other technologies, and includes maintenance service. With a combined geothermal-solar system, Bosch said many buildings can achieve zero net energy status, and a homeowner’s utility-supplied energy use will be minimal to none as they return excess solar-generated energy to the grid. The savings in utility electricity costs can be equal to or greater than the monthly ESS energy fee. The EcoSmart program delivers the value of energy efficient technologies without requiring upfront costs for the homeowner or builder.
The Bosch geothermal heat pumps installed at Whisper Valley will be connected from each home to an underground heat-exchange-loop infrastructure system, consisting of geothermal boreholes that utilize the constant temperatures several feet below the earth’s surface to provide heating and cooling. The homes will also use Bosch heat pump water heaters to supply whole house hot water, further leveraging the benefits of a geothermal solution.
Read more about how to generate electricity at home.
Companies: U.S. Department of Energy