HOT WATER HEATING SYSTEM
Hot water heating is the second largest energy use in a home
According to Department of Energy hot water heating is about 20% of a home’s energy bill. This is the second largest user of energy in a home behind heating and air conditioning. Reducing how much energy is used to heat hot water has large impact on a home’s energy bill.
Quality hot water heating system reduce energy use
Reducing energy use for hot water heating is not as simple as choosing what kind of water heater a home has. It takes a quality water heating system including:
high efficiency components
Benefits of a high quality hot water heating system
Beyond energy savings, there are other benefits to having a quality water heating system including:
quicker delivery of hot water to faucets and
more hot water in general
These types of synergies are more reasons why a green home is a more better built, higher quality home.
Reduce transmission losses through clustering baths/kitchen and water heater
The hot water heater is centrally located in basement directly underneath the kitchen and baths above it whenever feasible allowing. This designs in short pipe runs that provide hot water sooner at all taps and reduces the amount of heat lost in transmission.
Reduce transmission losses through extra thick pipe insulation on all hot water pipes
Believe it or not, hot water pipes are not required to be insulated. In a True Turtle home all hot water pipes are insulated with custom ¾” thick polyethylene insulation to a value of R5. This is not the wimpy pipe insulation you can cheaply pic up at Home Depot…it’s 2.5x the insulative value...meaning more hot water makes it to the faucet faster.
Reduce amount of hot water used through high efficiency appliances and fixtures
High efficiency Energy Star qualified dishwashers use 20-30% less water than the federal standard.
High efficiency Energy Star qualified clothes washer use 10% less than federal standard
Low flow WaterSense faucets use 31% less water
Low flow WaterSense shower heads use 50% less water
Energy savings through heat recapture – Drain waste recovery system
Every time you shower or run the dishwasher, the hot water that goes down the drain is lost energy.
A drain waste heat recovery system recaptures that energy and puts it to use.
Drain waste heat recovery equipment installed on that main drain transfers the heat from drain water and preheats the incoming main water supply. Raising the temperature of the incoming hot water lowers the amount of energy it takes to heat hot water.
True Turtle home’s are specifically designed so that all upper baths and the kitchen drain to a single main drain to maximize heat recapture.
Minimize Standby Losses
Drain waste recovery systems also allows a smaller hot water tank to be installed as it heats water faster; further reducing energy use by minimizing the amount of energy is needed to keep water hot in the tank 24/7.
High efficiency equipment – electric water tank
Older electric tank water heaters are commonly 80-90% efficient. Thankfully, the minimum federal standard for electric hot water heaters has been steadily raised by the US Department of Energy. In 2015 all electric tanks are mandated to be 96% efficient. We are already installing the new required minimum efficiency units.
We freely admit there are sexier options than a plain jane electric tank.
However, using a standard electric tank has the following benefits:
Avoids using combustion fuels in a home that can cause backdrafting issues
Can use solar PV to offset the energy use making the home net zero energy
Simplicity of operations and maintenance for long term durability
Cost effective for builder allowing funds to be spent on insulation, air sealing,
window upgrades and other envelope improvements
Ultra high efficiency equipment – heat pump hot water heater
Heat pump hot water heaters are hands down the most energy efficient ways to provide hot water to a home. Heat pumps do not make hot water…the transfer heat from the surrounding air into the water. Because they do not make heat they are at least 2x more efficient than the highest efficiency gas or electric hot water heaters either tank or on demand.
As you can see from the chart, efficiency of the heat pump hot water heater is double what all other types of heating, and the annual cost is competitive with the a solar PV array with electric back up.
Chart Stats from: Aceee.org