The term Net Zero is a perfect example of something that started out as fairly straight forward, only to be complicated later by personal interpretation. In this case, it was the whole ‘my building is greener than your building’ business that made things confusing.
And while I do enjoy a good-natured competition, especially when it tends to displace fossil fuels, the results of this ‘energetic expounding of interpretation’, have left outsiders scratching their heads.
In the simplest of definitions, a Net Zero home is a home that produces as much energy as it consumes. And while the term may sound quite unique, it’s not really as difficult a thing to achieve as one might think.
For example, if you were to build an all electric house, meaning no natural gas or propane is used, and then installed a solar array capable of producing as much electricity as the house consumes, then by definition, you have a Net Zero home.
Problems With Net Zero Homes
Imagine you were a perspective home buyer and were deciding between two homes of equal appeal, with one having the normal utility costs associated with daily living and the other being Net Zero. Which do you think you would choose – the home with or without utility bills?
Obviously, there is an appeal for Net Zero construction.
However, there are two caveats to this utility free living that need to be understood before endeavoring to do so.
The two main problems with Net Zero homes are :
- They have a higher than average construction cost
- They rely on the good graces of the electric utility
Both of these two problems can be detrimental to your Net Zero goal of providing as much power as you consume. And, unfortunately, while the initial construction costs are generally fixed (after occupancy is acquired), the whims of the electric utility are not.
There have been instances where homeowners were required to disconnect their costly arrays in order to stay connected to the electric grid.
Net Zero Construction Costs
One of the biggest surprises for me when building our new off-grid solar home, was the fact that the banks did not view the panels as adding any real value to the home. Consequently, they refused to include any costs related to the home-power system, into the construction loan.
In short, we paid for everything related to solar power up front and out of pocket.
That’s not fun!
It should also be noted that Net Zero homes generally have a higher level of efficiency than average. This means more insulation and top of the line energy saving appliances – both of which add to the cost of construction.
An argument can be made that these costs will be recovered through lower (or the lack of) utility bills. But forking over more at the beginning, for what appears to be less, can be very difficult.
Net Zero And The Grid
Imagine how you would feel after spending tens of thousands of dollars on a solar array only to be told that you must disconnect your investment.
This does happen.
The majority of Net Zero homes existing today are grid-tied, meaning they are connected to the electric utility. Point of fact, most Net Zero homes would not work without the direct support of the electric company. This is because household demand routinely exceeds system capacity.
Remember, a Net Zero home produces more energy than it consumes. However, this is measured over the course of a year, not at any given moment.
To understand this, imagine you were home cooking dinner (oven, two burners and the microwave) and your A/C turns on. In this scenario, your household demand could easily exceed 10,000 watts. Unfortunately, your solar array is only capable of producing 5,000 watts. So what keeps your house going? Where does that extra energy come from?
It comes from your electric company.
But if we are taking energy from the electric company, then how does that meet the definition of producing more energy than is consumed?
Because in the off times where your household demand is low – say 1,000 watts of demand – your panels are still producing 5,000 watts. This extra 4,000 watts (hypothetical) is then shared with the electric utility and your home is ‘credited’ for it.
And if your ‘credited’ energy is enough to help you exceed yearly demand, then your home is considered Net Zero.
Bluntly speaking, in a grid-tied situation, your home is utilizing the existing infrastructure of the electric utility – without it, your home would not work. And it is because your home depends on this infrastructure that the problem associated with Net Zero becomes clear.
Should your utility decide that your solar panels are a detriment to the operations of electric grid, then you will be required to disconnect them… and your notable investment will be for naught!
Clearly, that would be problematic for most of us.
Net Zero homes are something of an enigma. I think anyone can relate to the desirable aspect of having all the power you need, when you need it, without the monthly bill. But in the same regard, what would happen if every home were Net Zero? Who then would pay for infrastructure?
Most people are savvy enough to understand that every business relies on a certain amount of cash flow. From a personal perspective, I can assure you that I would be quite upset if even 10% of my cash flow disappeared!
For this reason, it is my opinion that the current business model where Net Zero homes are able to utilize infrastructure without regular monetary input will not last. It is simply not economically feasible to do so – especially on a larger scale.
Please do not misunderstand. I LOVE solar!!!
Obviously, my family and I would not be living the solar life if there was any lack of passion or conviction regarding photovoltaics. But I am mature enough to understand that in order for any relationship to last, it must be mutually beneficial.
And while power companies do benefit from being able to monetize the extra power that your panels provide, it’s easy to understand that in order for them to survive, they still need incoming revenue – revenue that would disappear if every home were Net Zero.
The Future Of Home Power
So where do we go from here? What exactly will be the future of home power?
That is difficult to forecast. But I think the answer may lay in energy storage.
What if Net Zero homes were able to store the extra energy their solar panels produced during the day, instead of selling it back to the power utility?
If enough energy was stored, then wouldn’t this allow them to bypass the power grid completely?
The ability to generate enough power to run a household gets easier by the day. And with energy storage expanding rapidly in both capacity and lower costs, it’s easy to foresee a point where these two technologies intersect.
When this happens, people will have a choice; buy a home that requires supplemental energy input or a pay a little more for a home that provides all of its own power.
It may be that in the near future, most homes will be Net Zero.