The first net zero energy townhouse complex in the US was built by Ichijo USA in a collaboration with the Port Blakely community and the City of Issaquah. It met and even surpassed expectations, and some of the highlights are fascinating:
- Over 562.8 kWh was generated above what zHome consumed, and was put back onto the grid between April 2013 and April 2015.
- zHome exceeded net zero energy by 3.5 percent, or almost $54 worth of electricity.
- PV arrays range from 4.8 kW to 7.2 kW and performed 24% better than modeled.
- The goal of reducing water consumption by 70% was achieved. The average zHome per capita daily consumption was 16.07 gallons from the utility and 11.46 gallons of rain water.
How many sizes of homes do you build and what are the costs?
zHome units sold at the lowest price point in the history of Ichijo, but they were all near market rate. The homes range from $244,000 to $600,000 with sizes ranging from a studio to a three-bedroom. Projects outside of zHome vary greatly. Ichijo builds multifamily townhouses and single family houses. As a result the square footage of our projects ranges from 1,800-3,800 square feet and price points range from $425,000 to $1.6 million.
What are the typical utility costs for one of your homes?
zHome has a net-zero utility cost on an annual basis. This means that electrically the homes are net-zero, and with the production incentive of power being put back onto the grid, water and sewage costs end up being offset. However, this does depend on the whether or not the homeowner applies revenues towards their utilities. Sun Ridge is a community in Issaquah that is active under construction. We are building the homes with solar standard, which translates to a 30 percent to 50 percent reduction in costs of utility bills. Other communities without the solar standard option have 10 percent to 15 percent savings from energy performance features like increased insulation, efficient appliances, high efficient heating systems, and LED lighting.
Does each house have its own rooftop PV solar system, and what is the size?
zHome solar array sizes depend on the square footage of individual homes from 4.6 Kw to 7.2 Kw. The majority of homes we build have a 3.5 kW array, but our highest efficiency homes have a 10 kW array and our other communities’ homes aren’t built with solar PV, but all homes are prewired for solar. We recently had a homeowner add-on solar PV as a standard upgrade option.
What solar panel manufacturer do you use, or is there more than one?
All zHome solar panels came from SolarWorld in Portland, Oregon. We use a variety of suppliers for our other projects ranging from out-of-state modules to in-state Itek modules. The manufacturers we use depend on the size of the array, community, and specific home owner requests depending upon the available incentives.
What energy efficiency measures are included in each home?
There are a wide range of efficiency measures we employ on our projects depending on the type of home. For zHome we used a geothermal heating system and our insulation was double the required code. The building of zHome was the most rigorous process I’ve ever been through. We used only regional materials, recycled materials where available and all green building industry standards were applied. The development was the first Salmon Safe certified residential project in Washington State and included FSC certified lumber, no PVC and low or zero VOC finishes on all surfaces. Ichijo is now taking all of the energy related performance items and implementing them into current projects. The consumer can really see their return on investment when it comes to items like solar panels and the 420% efficient heating system we used in zHome.
All of the homes we build include what we call our advanced envelope. This includes increased air tightness, at a benchmark three times the current code, increased insulation, 10% above the required code and high performance windows.
In a fact sheet, it says that one of your home solar systems produced 24% more than what was modeled. What factors contributed to this production?
Every system was designed and installed for optimal performance. Most of our homes exceed their expected
production by about 10%, but in this case we think the 24% increase was due to environmental factors.
Do your homes collect rainwater, and if so, what can it be used for?
The zHome project included a rainwater collection system which used the water for toilets, washing clothes and temporary irrigation. We have since installed one other collection system at a new project for the same uses.
Will your homes employ electricity storage in the form of onsite battery systems?
We have found that the battery technology does not align for full off the grid demand. As a result we don’t see it as being cost-effective because our consumers won’t see a return on investment. In this climate, especially with the length of nights in Washington during the winter, a battery would only power the home and all its devices for six to eight hours with current technology. While we are capable and willing to install, we have not yet seen a consumer demand for this technology.
Does each home have an energy management system utilizing software?
Our thermostats use Nest technology and our solar production has standard monitoring, but both of these are standard management systems. Our homeowners have the ability to add their own apps to the thermostat if they want. We have installed whole house intercom/communication systems and lighting control packages, but only at the request of the end consumer.
What kind of materials are used in your homes and are they environmentally friendly?
For zHome, as I mentioned before, we used only regional materials, recycled materials where available and exceeded all green building industry standards were applied. The development was the first Salmon Safe certified residential project in Washington State and included FSC certified lumber, no PVC, and low or zero VOC finishes on all surfaces. The project was a green building project pioneer and became the case study that developed the “Emerald Star” Built Green certification which is the highest achievement, similar to LEED Platinum. We also made sure to uphold a 90% recycling rate for all waste leaving the job site.
zHome really helped me to see just how much waste is generated from job sites. We now uphold this standard for all job sites by implementing source separation and keeping an eye on the chain of custody for materials leaving the site. Our current Sun Ridge project has attained the 5-Star Built Green rating and all of our homes are built using the same environmentally friendly building practices.
How many homes have you constructed in 2015, and how many do you expect to build in 2016?
We are actively working on 45 homes right now. We expect to close about 35 this year and in 2016 we expect to close about 70.
In which geographic areas are you currently building homes?
We’re currently building homes throughout the greater Seattle area. We have 7 active job sites right now with one in Redmond, two in Sammamish, one in Issaquah and three in Kent.
How much might a resident of one of your homes expect to save in energy costs in one year?
Residents of zHome can expect to save 100% of their energy costs because the project is net-zero. Our other homes range from 10 to 50% savings depending on the project type and model of the home.
What are some of your plans as a company for the next three to five years?
We plan to continue establishing ourselves as industry leaders in the greater Seattle market and providing energy-efficient homes standard. We currently are building homes in Seattle, Washington and Australia and are looking at expanding to other markets in the United States.
Image Credit: Ichijo USA