Sustainable Design Blog

NET ZERO, AND LOVIN' IT!

Hi everybody, and happy 2017! I hope you had a wonderful holiday season, and were able to celebrate the New Year with good people and good times.

Speaking of, I wanted to kick the year off with a little celebration of my own - because we just received report back on our 2016 Gold LEED certified nature center at Audubon - and it turns out that just by existing, our building is contributing to solving our energy crisis!

Similar: How to Choose a Solar Power System for Your Home or Business

I would like to use this blog to give you an update on one of our recently completed projects - the Audubon Nature Center located at the celery fields in Sarasota, Florida (see gallery here).

The building has been open for a little more than a year, and we have been gathering data on its electrical use. As I reported earlier, the building is a net zero energy building, which means it creates more electricity than it uses.  

So, now we have a full year's worth of data to share, and even a break down of how the power was consumed.

Below is a table which shows the actual annual power demand and actual solar PV generation for the Nature Center. Total demand is 15,107 kWh per year. And, according to a study conducted by the EIA (US Energy Information Administration), that is almost identical to the energy consumption in the average household here in Florida and an average of nine other nearby states.

Download the resource: How to Design a Green Home

The electrical system exports more than 25% power (4,000 kWh) than it consumes (15,000 kWh)!  By making significantly more energy than it consumes, it not only offsets 100% of it carbon footprint caused by electrical generation, but it helps others do the same by providing clean, renewable energy to the electrical power grid.  So, the building has exceeded net zero performance and is operating as a net positive facility.  

One thing to remember - this is NOT just about solar power. Net Zero Energy starts with the building envelope, and carries on with passive design features that put conservation first. Then, one does not need to create as much of it its own energy to become net zero or net positive.

The building has a highly efficient building envelope including insulated concrete form walls and double glazed insulated low E coded windows.

Plus, the building orientation and wraparound covered porches provide shading 100% of the time. The building has a sealed attic with spray foam insulation on the underside of the roof deck.

The building creates its own energy by using its 11.2 KW's PV solar array mounted on it south facing roof.  

But back to the results, because I find them to be quite fascinating.

It is no surprise that the HVAC electrical use is the largest use in the building. What I find interesting is that the plug load electrical use is the second largest component of energy used in the building.  

Plug loads are those things inside the building that the occupants use that demand electricity.  It could be the coffee pot, copy machine, printer or a desk lamp or a little tabletop fan- things like that. These are electrical uses that are not well defined in the design phase and they are hard to estimate and difficult to control.  Plug loads are one of the main reasons why net zero energy needs to be proven through actual use and not just modeled/predicted.

The Audubon Nature Center received LEED-NC Gold Certification in January of 2016.   The high-performance design has actually been exceeding the projected energy performance predicted by the energy modeling.  And, in Oct 2016, the project won the prestigious USGBC Florida Gulf Coast Chapter Outstanding LEED for New Construction/Non-Profit Award for the region.

Try also: Does the Cost of Solar Energy Outweigh the Benefits?

CONCLUSION:

Forget about Net Zero Energy.... Let's talk about Net Positive energy design! It is possible, even on a modest budget.  

Wouldn’t it be great if every new building provided more energy than it consumed, so new construction actually reduced the overall power demand in a neighborhood or region instead of increasing the demand? Some people are already doing it, and their making it easier for you and your friends and family to exist and prosper.  

What if architecture added resources instead of consuming them? Why don't we make that our goal? If you're interested, I'm happy to walk you through a consultation for your next build to see if sustainability is a worthy investment! Click HERE:

How much does it cost to turn the sun into electricity, and is it worth it for my Florida building?

According to the Solar Energy Industries Association, a typical residential system should lower your electric bills by 25% to 50%. The a verage household pays about $110 a month for electricity, according to the Energy Department, so a solar-panel system should save you between $300 and $600 a year.

Not bad....

Finding such savings and a shorter payback time than I expected when I first started looking into the subject, led me to doing further research on the use of solar panels for residential energy in sunny Florida.

However, doing so opened a can of political worms I was hoping to avoid, because it turns out that our laws are tilting the scales in ways people don't realize.

MORE LIKE THIS: How to Choose a Solar Power System for your Home or Business

Why squander potential like this?

Sunny Florida has plenty of solar energy potential so why haven't we adopted a more aggressive stance on generating our own clean, affordable power?  We're at a great advantage because of where we are, as there are no excessively long payback periods for installation of solar panels in sunny southern states.

Something is holding us back.... But what?

It was interesting to find that Florida ranks third for solar potential according to the Solar Energy Industries Association (SEIA), Florida, but only placed between 14th and 18th (research varies) on the list of largest solar installers. (resource)

The payback period:

If you live in a state where the cost for electricity is in the higher rate tiers, the payback can be as little as 2-4 years.  However, it should be noted that the time-frame will vary greatly depending on the size of your system, the cost of your system, and future swings in local electricity costs.

Florida happens to be a state where we are slightly above the average price per kilowatt hour when compared to other states, so it's a little quicker for us.

The Argument against solar

Utility companies have been saying residential solar systems cost them money because solar owners pay less in monthly electricity bills, yet expect their utility to step in and deliver power whenever their system doesn’t, which puts unexpected stress on their systems.

Solar advocates, on the other hand, say residential solar systems save utilities money by taking pressure off the electrical grid.

So, who do we listen to, and who are our elected officials supporting? And, is it any surprise that those making money off of our dependence on non-renewable energy sources are advocating against solar?

Not to me, but I kept digging anyway.

How to reduce up-front costs

Although payback for installing solar panels is becoming more affordable all the time, small systems still remain too expensive for most homeowners and businesses. Cheap electricity from fossil fuels and nuclear power gives property owners less reason to buy a system.

In some states, solar companies lease panels to consumers so they avoid the up-front costs of the panels.  

And, actually, I found data that covered four-fifths of the United State's solar capacity in 2014, and it stated that almost two-thirds of residential solar systems were owned by a third-party solar company. (resource)

HOW POLICY IS TILTING THE SCALES:

Surprisingly, Florida hasn’t opened the door to these kinds of third-party ownership arrangements, which means we don't have the same kind of access to clean energy as the states that do.

We actually have legislation that directly opposes it. Under the Florida Constitution, only utilities can sell directly to consumers.

In addition to not having access directly because of the financial implications, it also means that landlords of commercial and residential buildings who have installed solar panels on the roofs of their properties cannot sell the electricity to their tenants.

It's clear to me that our current regulations are hampering deployment of solar in Florida, which is incredibly frustrating for somebody who has dedicated their career to implementing sustainable design.

Think about it... How many people do you know who are renting their homes? And do you realize how many commercial buildings there are that lease space to their tennants (hint: it's pretty much ALL of them)?

What else our state is not doing

Florida Power and Light (FPL) offers rebates to residential customers who implement certain energy efficiency improvements in eligible homes. There are HVAC rebates and incentives for upgrading ceiling or roof insulation, or installing a reflective roof.

Strangely, though, there are no state rebates for solar panels in Florida.

There are, however, Federal Income Tax Credits for Energy Efficiency that includes solar generated energy.  Tax credits for Solar Energy Systems are available at 30% through December 31, 2019.

If you have a pool, however...

That takes us to Plan B: Solar panels for swimming pools.  There are approximately 800,000 swimming pools (including above-ground) in Florida, and most of them must be heated during the cooler months to maintain comfortable swimming conditions.

An unheated pool will stay generally at about the average outdoor temperature, which may be in the 50’s during the winter months here in Sarasota.  For most people comfortable pool water temperatures are 78°F to 82°F in spring and fall and 76°F to 78°F in winter.

Average yearly cost for heating a residential pool in Florida is $1,450 using electrical resistance, $500 using an electric heat pump, and $580 using natural gas. Liquid propane would cost the same as electrical resistance. (resource)

A typical solar heating system costs from $2,000 to $4,000 installed. Costs vary based upon the ease of installation, type of financing, location of pool in north or south, length of pool season desired and building code requirements.

The good news, compared with average fossil fuel heating, a solar pool heater offers a favorable payback of 1.5 to 7 years. In addition, the solar pool heating industry in Florida is mature. It has numerous distributors and contractors and a track-record of over 20 years of experience, and with proper care a system can last you 10 to 15 years.

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CONCLUSION:

Change never comes easy, even when it means saving our species from extinction. But we must take steps that lead us to total sustainability, or we won't be able to reverse the calamities caused by our dependence on limited and polluting energy sources.

I say that we should make some noise and make these issues known to our elected officials, so they know we're serious about enacting change that will benefit ALL of us.

Meanwhile, please enjoy a relaxing dip in your solar powered pool!

Interested in learning more about green home design? Check out this handy ebook my firm published about why it's an absolute MUST:

What are some systems for solar power generation that I should consider?

People come to our firm for green design because it's a very personal mission of ours to contribute to the sustainability of our planet and the preservation of our species. We also design beautiful buildings, if I do say so myself...

So, it's not all that uncommon to get questions about how to include solar power, our abundant and clean resource, in the overall design.

First some basics:

Solar panels (aka Photovoltaic Panels, aka PV) make electricity from the sun. They produce DC power, like batteries, which can be used directly to charge your electric car, stored in a large battery system, or be converted to AC power and used directly in your home or business.

The cost of PV has been dropping steadily for the past decade. Our first PV install was in 2003, and the cost was round 11 cents per watt.  Now PV is running around 3.5 cents per watt, and even less for larger installations

Here are some other useful facts that will help you narrow in on the right system for you.

1. Battery vs AC vs Net Metering

Battery storage is not required, and although battery storage systems are getting better, technology still needs improvement. You may have heard of the Powerwall, by Tesla. It is a rechargeable lithium-ion battery product for home or small commercial use. It stores electricity for consumption, load shifting, and backup power.  

Converting the DC power to AC and using the power directly is still the best option. Net metering is also very helpful, but eligibility varies greatly depending on the location of the property. Ideally, net metering is provided by your local power company and allows you to sell the power you make back into the grid at the same price that you pay to buy power from the power company.

Be aware- Sometimes the utility company sells electricity at one rate but buys is back at lower rate. Since many power companies are monopolies, and exist for the benefit of their shareholders, not their customers, you need to check with your local utility to determine if they have a net metering option, and exactly what the details are.   A good net metering program allows you to use the utility grid as your "battery" to store the excess power you make on site.  

If you have true net metering (1:1 buy/sell pricing) putting PV on your home or business makes great sense.  If you do not have access to net metering, you want to size your PV system so it makes some or most of power that you need, but does not typically make more power than you would normally use.

Net metering gives you a better opportunity to achieve net zero energy if that is your goal.  You can size your PV system to make more power than you need at some times of the day or year, so you have excess power "stored" in the grid to use when you cannot make all the power that you need, such as in the hottest part of the summer in Florida when your electrical loads are the highest.  

2.New construction

For new construction, considering the price of PV and the rising cost of electricity, the best thing to do is include your PV in your construction budget and install it when the building is constructed. It is a great investment with a strong return.

Can't afford it today, but want to stack the deck in your favor?

The next best thing is to set up your new building to be solar ready.  This means positioning the building so it can gather the sun when PV panels are installed in the future. Provide South facing, sloping roofs that are set up for panels to be installed later.  A standing seam metal roof is best for mounting, but other roofs can be accommodated.

If your building design wants to have a flat roof, be sure there are no other structures on the building that could prevent the sun from shining directly on the roof, such as stair tower, tall parapet walls, etc.  Of course your roofs will be light in color to reflect the heat of the sun, but that topic was covered in an earlier blog (Green roofing system selection by Carlson Studio Architecture). Typically, proper "solar ready" orientation will tend to create a building that has it long sides facing North and south, with it short sides facing east and west.  

Roofs oriented within 15 degrees of due south are recommend in the LEED for Homes criteria. The Birch Haven residence designed by Carlson Studio in southwestern lower Michigan is a good example of setting the home up properly for solar panels.  The site boundaries were oriented 35 degrees west of due south.

This was less than optimum, so we created a design that allowed the main roof of the home to be facing only 15 degrees west of due south, while the interior of the home was still aligned with the site boundaries to take full advantage of the build-able area of the site and the views.  And, we included the PV panels into the construction budget, so a 7KW PV system is about to be installed on the roof as the project is nearing completion.  

And if you're thinking about the long-term value of your investment, you should know that buildings that are"solar ready" are going to be worth more than those that are not, as noted by this study by the Office of Energy Efficiency and Renewable Energy (EERE) and personalized to your situation with this PV home value calculator by SolarSimplified.org.

3. Existing Buildings

For existing buildings, everything discussed above still applies, but you may have been dealt a less than ideal situation based on your building's orientation. Hopefully you did not just buy a home or office building with no way to retrofit solar panels onto it.

Get together with your experienced sustainable architect (Carlson) and have them evaluate the possibilities for your existing building.  The panels are lightweight, so most existing structures can support them, and wiring from the roof to the electrical room is just being able to get the conduit runs to work through the existing building.  

CONCLUSION:

PV panels can last 25 years of longer. The initial payback ROI can be as short as 5-10 years, depending on your net metering options, and the cost of your electricity. There is still a 30% Federal tax credit available too.  And the cost of energy is rising.

Of course, our planet is also wasting away with the excessive usage of fossil fuels and other non-renewable sources. Now is the time to get PV on your home or office building, or at the very least, set yourself up to succeed and save money in the near future by being prepared to add PV at any time.

Interested in learning more? Set up a free green architectural design consultation with Carlson Studio Architecture today!