The Village Green

A blog about how Canadians can achieve energy independence by powering down and then powering up the right way.

"(energy) follows laws of its own – the laws of thermodynamics, notably – which are not the same as the laws of economics, and when the two sets of laws come into conflict, the laws of thermodynamics win every time".  - John Michael Greer

While Top 5 Things You Can Do To Make Your Home Green type articles have their place, I believe what we need instead are good principles that are immutable, that stay constant with time.  Because when we get the core principles right, everything else tends to follow.  This article is about some of those core principles. 

Physical laws

As Mr. Greer points out, energy is governed by physical laws.  And when physical laws run into economic laws, the physical laws will eventually win.  

What does this have to do with having an energy efficient home?  

Everything.  

As we look at making our homes and buildings more efficient, we’re going to need a process – a methodology – for thinking about efficiency and making decisions.  By having a process and a method founded on good principles, we ensure that our energy efficiency efforts aren’t slap-dash - solar panels here and there and everywhere – but instead work toward a goal in a coherent way.  

In this, we’re lucky; energy acts in accordance with specific physical laws.  Knowing some rudimentary things about these physical principals enables us to develop the principles we need in order to make our homes more energy efficient. 

Kilowatt ours not Kilowatt Hours 

Whenever we use energy or capture it - like by burning fossil fuels to heat a room or using solar panels to generate electricity for our off-the-grid home - some part of it spins off in such a way that we can’t use it.  The laws of thermodynamics guarantee this.  

This is why generating even “green” energy and “renewable” energy will be less effective and less efficient than not using energy in the first place.  For our purposes, being less efficient means losing money.  

This is why we need to always think first about the energy we don’t use instead of the energy we can use efficiently and greenly.  Think of this as “kilowatt ours” instead of kilowatt hours.  We want to maximize “kilowatt ours”.  When we maximize kilowatt ours, we get the financial benefit instead of the financial benefit going to the electricity company.  

Our first strategy will always be to not use energy in the first place.  What does this mean?  It means our green home strategy will generally start with things like insulation, weather-proofing and having energy efficient doors and windows.  Putting in all that cool new technology like geothermal systems and solar panels comes later.  

So what do these priorities look like?  Here’s the four steps we take in our work with clients.  

Step 1:  Reducing the need for energy in the first place:   

We always want to make sure that we reduce our need for energy in the first place, because a unit of energy not used is going to be more valuable than a unit of energy used or generated efficiently.  The laws of physics govern this principle.  For your home, this means ensuring that your foundation, walls and attic are well insulated and your doors and windows well sealed.  Caulking, weather stripping and insulation, all things considered, are cheap.   

This is where we start.  Always.  

Step 2: Recycling the energy you have already used:  

There are now various energy recycling technologies available to homeowners on the marketplace.  They’re well worth the money.  

A grey water drain heat recovery unit on your main plumbing stack has no moving parts, is easy to install, will last the life of your plumbing system and will recapture 50% or more of the heat contained in the hot water used for baths, showers and dish washing that goes down your drain.  Because a drain heat recovery unit is built out of copper, its cost varies dramatically with the price of copper as a commodity.  In general, they can be installed for about $1,500 and will last decades. 

Meanwhile, a Heat Recovery Ventilator (HRV) will both reduce energy consumption and bring fresh air into your home.  A heat recovery core in the HRV pre-conditions incoming fresh air with heat or cooling in the stale air it removes from your home.  An upgraded HRV is an ERV or Energy Recovery Ventilator which will also de-humidify in-coming humid air in the summer.  Because humid air is denser than dry air, it’s more difficult to cool which increases your air conditioning costs.  Either way, think of an HRV or ERV as the “lungs” of your home.  They can be installed starting at around $3,500.

Step 3:  We want to use energy only when we need to:  

When we need to use energy, we want to ensure that we use it only when we need to.  There’s several ways this can be done.  

Timers can help us turn things on and off in a smart way.  This will become more important with the introduction of time-of-day electricity metering where electricity will cost more at peak times than off-peak times.  

Meanwhile, kill-switches and power bars can enable us to turn off the current in parts of our home when we don’t need it.  “Phantom load”, the current that runs through all of our consumer electronics even when they are turned “off” can comprise as much as 8% of total electricity use in the typical home.  What’s more, this situation will get worse as electronics become more “sophisticated”.  

Finally, we can design our homes to store energy – mostly as heat or cooling – by integrating passive design elements that enable us to use the sun in really smart ways and storage tanks that can be hooked up to geothermal heat pumps.   In Europe there’s an entire design protocol based on passive design.  Combined with the right control systems, heat storage can enable us to generate the heating and cooling for our buildings when energy costs are lowest.  

Step 4:  Using and generating energy in the most efficient way possible:   

Finally, we’re on to renewable energy and efficiency systems.   From solar water heating to geothermal heating and cooling systems, future-proofed homes will eventually be retrofitted for renewable energy systems.   

Power down and power up 

Perhaps you’ve noticed that renewable energy is the last step in our priority tree. This is not to dismiss the need for technology and new systems; clearly we’re going to need a range of strategies, systems and approaches as we collectively power down and power back up the right way.  

However what we need before the “green stuff” are basic principles that tell us what green stuff we need in the first place and how to put it together in ways that make the most sense.

Gabriel Draven, Village Technologies