Purpose of ZNE

Simplicity and style in this net-zero German Passive House.

A ZNE home is one where the value of the energy produced by on-site renewable energy resources is equal to the value of grid energy consumed annually. Net-zero is measured by the Time Dependent Valuation (TDV) Metric. TDV is the cost-effectiveness and energy valuation methodology used in development and implementation of California’s Title 24 Building code. The TDV is a metric of  energy cost effectiveness. TDV evaluates whether a building-code requirement will save consumers
money on their utility bill over the life of a new home compared to no requirement.

Features of a ZNE Home

Fortunately, there are proven construction methods for every climate that allow builders to construct comfortable, efficient, and healthy homes. These best practices don’t require hard-to-find materials or a change in construction sequence. ZNE best practices require a “whole house” approach to building that recognizes how each part of the home works together to provide a comfortable, safe, and durable shelter. These best practices include the following.

  • Superior insulation R-value and installation
  • Airtight building construction
  • Efficient and correctly sized HVAC systems
  • Shading and reflective surfaces to minimize air conditioning
  • Well-designed mechanical ventilation system
  • Photovoltaic solar electricity

How to afford a ZNE Home

Who needs 20 different roof surfaces and 20 different wall surfaces?

There are many features of modern homes that serve no purpose other than to copy antiquated building habits of the past, such. For example homes that, newly built, look like they have two or more additions. Why do we need to build a home that mimics a farm house with five editions, built to accommodate a growing family of six children are more? Additions are a nightmare to insulate and airseal. Same problem for new homes that look like they were modified over the years with the addition after addition.
Why do we need fireplaces in new homes? Many of the tragedies of carbon monoxide poisoning happen because of fireplaces. Fireplaces burn wood at 25% efficiency or less. Fireplaces are also a large air leakage problem whether they are burning or idle. Plus they cost a lot of money to build.
Think of the future savings from utility costs that are rising rapidly these days. Think of the environmental benefits of building a home that produces as much energy as it consumes. You can achieve the status, if that’s what you’re seeking, from rooftop PV solar collectors and around electric-vehicle charging station.
We don’t need to mindlessly copy the building mistakes of the past.