Analyzing Energy Use

Here is a snapshot of the preliminary energy data received from our eMonitor system. The eMonitor is connected to each of the home's circuits and allows us to remotely see real-time energy use.

Before the home was constructed, the energy use calculations for the New Norris House (1008 sf) were projected at 40.13 kBTUs/sf/year OR 12.05 kWh/sf/year. Using our collected data, the actual total energy use is 23.8 kWH per day OR 8.62 kWh/sf/year (based on 6 months of data from Jul 01 2011 – Jan 26 2012) - significantly less than projected and 61.3% less than the typical US household.

Data from the New Norris House will be collected for an entire year. This data will be used to refine the prototype and disseminated for life-cycle assessment studies.

Phase IV Water Monitoring

Now that our water systems are up and running, it's time to begin the monitoring and analysis process. My task as a graduate assistant is to formalize a sampling and analysis protocol for testing water quality on both the supply side and the waste water side.

A little about me: My name is Valerie Friedmann and I am in my third year of studies as a graduate student in landscape architecture at UTK. My role in the New Norris House project began as a landscape architecture student consultant in the spring of 2010. I began by refining the conceptual landscape design, and continued working on the project to see it through the construction and installation phases. Last summer, I worked with a group of UTK students to finalize construction documents, order materials, and construct the landscape elements. Now that our landscape system is online with the home's rainwater overflow and greywater discharge systems, I am very excited to determine the efficacy of the landscape systems in mediating the quality of the greywater and the flow, velocity, and erosion potential of the rainwater.

Back to the monitoring process:

On the water supply side, our design includes a rainwater harvesting system that collects rainwater from the roof of the home and stores it in a 400 gallon cistern. The water is filtered and treated with UV and used for non-potable sources in the home. We have a temporary permit to allow rainwater to be used in the home, and we are testing to compare the rainwater composition pre- and post-treatment to the City of Norris municipal water supply.

Our goal is 01) to learn if the rainwater quality we are collecting and treating would produce water that is safe for use as a potable source and 02) how the water quality compares to the city's water quality. The City of Norris revised its ordinances to allow the systems to work and be plumbed as such in the New Norris Home while UTK owns the home. Results may allow extension of the permit to a future owner, and perhaps other town residents. A second test we are interested in concerns the greywater. We have designed and installed a greywater treatment garden, and we would like to sample the greywater as it leaves the house and at various distances from where it enters the greywater treatment bed. The goal here is to see if pollutants from the greywater are successfully being mediated in the bed. We currently have a temporary State Operation Permit from the Tennessee Department of Environment and Conservation (TDEC) that allows us to collect, treat and release greywater in the beds; this will expire after three years or when UTK sells the property. TDEC has been very supportive and is interested in the results of the study and its potential to effect future state policies.

Image Credit: Ken McCown

We are currently working with TDEC officials and UTK professors from the Department of Biosystems Engineering to develop our testing protocol for both rainwater and greywater analysis. I will be posting updates on our process and results throughout the semester, so stay tuned!

Monitoring Equipment

Thanks to Tony and Philip with ORNL for their all their help to setup our monitoring efforts for the house! Data is coming in and we hope to share some tidbits soon!

Rainwater System

I am pleased to announce that our rainwater system, although dry as a bone currently, is physically in place. Many thanks to our sub-contractors with Scott's Plumbing who have been hard at work for the past 3 days to complete the installation.

Several items still remain to be completed, however, before we can start washing clothes and flushing toilets with reclaimed water. First, the gutters need to go on. Second, city ordinances still need to be officially adopted that make what we are doing legal in the City of Norris. And third, the system needs to be primed and commissioned!

We are estimating this work to be done by mid-June. The legal process to adopt new city ordinances requires several readings and subsequent approvals, as well as a final public hearing.

Installation in progress. Cistern [bottom left], pump and controller [middle], and filters [right]

Multiple water meters installed in-line will allow us to measure how much rainwater is used in the house and how much city water had to be supplied to supplement. Other important factors include total rainfall (used to calculate how much rain passed through the system and was diverted as storm-water), as well as the total city water use (to indicate how much water was used specifically by potable fixtures.

Monitoring NNH Performance

We recently met with Jeff Christian (Director, Buildings Technology Center at Oak Ridge National Laboratory) to get an expert's opinion on determining a strategy to monitor the performance of the New Norris House. We discussed some general areas of focus: temperature, humidity, energy use, daylight, and air/water quality testing. In each case, a different approach to monitoring is to be considered. Jeff was able to show us some useful examples of testing instruments, including thermocouples and thermistors, current transducers, data loggers, pyranometers, etc., but encouraged that we take a close look at our personal monitoring goals and design an instrumentation plan with the exact equipment that best suits our needs. He also extended an invitation to his lab where he could help guide us in constructing our desired testing equipment.

The level of detail that can be monitored is seemingly infinite, so part of our challenge is to pose specific questions and set attainable testing goals that will still acquire enough data for a meaningful study. While our immediate focus remains fixed on the NNH, these monitoring studies could potentially apply to a much larger scope. If we can use our comprehensive data to illustrate the superior performance of the NNH in terms of sustainability, then we can begin comparative studies with older homes in the Norris community as an incentive for homeowners to retrofit these less efficient houses with similar sustainable technology.