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Renewable Energy System
Basics
Recent
Projects
2008
2007
2006
2005
2004
2003
Financial Incentives
PV History
Contact Us
Politics & Philosophy
News
FAQs
Andy Cochrane
Certification No. 031508-18
SolarWashington.org
NW Eco Building Guild
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Frequently Asked Questions
Will Solar Work for You?
The most common
question we are asked is, “I’m interested in solar power for my home
(or business), but I’m not sure if it works here or what it costs.”
We are glad you’ve taken the time to review this information sheet.
We’ll try to answer as many questions as we can right here. Then
when you call us, you’ll be even better informed.
First things
first, yes, solar power works just very well in our area. Here on
the north Olympic and Kitsap Peninsulas we average approximately 3.5
hours of full sun per day. That is about 70% of the sun resources
of southern California. However, unlike southern California most of
our sun comes in the summertime when our electricity needs are
lower, especially if your home has been designed to not require air
conditioning. If your system is tied to the grid, you can sell that
electricity back to the Californians during their peak energy
usage.
Net metering
regulations have dramatically improved the average person’s ability
to create and use their own solar power. Here in the northwest our
peak energy usage is typically during the wintertime when the days
are shortest, while our peak sunny days are in the summertime. With
net metering, it doesn’t matter. Net metering allows us to earn
credits in the summertime with our grid tied solar pv system and
sell those credits back to the utility in the fall as the days get
shorter and our energy needs start rising again. During the winter
when your solar panels aren’t producing as much power the grid acts
as your “battery” providing steady, reliable power. With net
metering you also save the expense and maintenance headaches that go
along with batteries. Batteries add approximately $5k - $10k to the
cost of the system and must be replaced every few years. We
generally discourage the use of batteries.
We can formally
determine the potential of your home or business for solar power
through a Site Evaluation
of your home or business (see #11 below). But we’ll give you some
basic facts now so that you can get a feel for your site’s solar
resource.
First, you’ll
need a roof with a good
southern exposure
or a
clear sunny area
on your property. It is best if the area is not shaded during the
day, but areas that receive sun from 9 am – 3 pm are still good
candidates. The best roof
pitch is
5:12 to 12:12. If you have a flat roof, or a roof that is facing
east or west, it is possible to orient the panels south through the
use of adjustable racking systems. As a rough rule of thumb, it
takes approximately 90 sq.
feet of roof area to install a 1 kw solar pv system
(90 sq. ft. = 1 kilowatt (kw) of installed system).
.jpg)
2.16 kw
system with panels racked up on an outbuilding in Glen Cove outside
Port Townsend
Yes, if a roof
is undesirable for solar panels, a
ground mounted
system is often
a good solution. We can mount the solar panels either on a single
pole or a multiple legged strut system that is secured to the
ground. These systems are a little more expensive than roof mounted
systems because of the additional labor and materials necessary.
Those interested in a super efficient ground mount system that
harvests the most energy from a small area may want to consider a
solar tracker
to keep your pole-mounted panels at the optimum angle throughout the
day and during the various seasons. Be aware that the addition of a
tracking device adds a motorized component to an otherwise
maintenance free system.
.jpg)
Ground
mounted 2.16 kw system in Bremerton with multi-legged struts.
This system
works well for larger ground mounted system and is adaptable to
uneven ground.
Ok, so you’ve
got a sunny spot picked out.
How much energy
over the course of an average year can you expect to generate with
your solar pv system? Are you ready for some math? Each 1 kw of
installed solar panels generate approximately 1,000 to 1,200
kilowatt hours (kwh) of electricity over the course of an average
year on the north Olympic and Kitsap Peninsulas (1 kw installed =
1,000 to 1,200 kwh per year). Sites with full sun where the solar panels are
oriented due south should expect to be at the upper end of this
range. Calculate your roof area and multiply it by this figure and
you’ll have an idea of the maximum power a pv system on your roof
could generate.
You should
review your power bill
to get an idea of how much power you are currently consuming over
the course of the year. Your utility bill will express your energy
consumption in kilowatt hours (kwh) per day, month, or year. You
may be surprised to see how much energy you use and how big a solar
pv system you would need to satisfy 100% of your energy needs.
However the economics of the available financial incentives allow
you to cover your annual electricity costs with a smaller system.
You should
first consider reducing your overall power demand through
conservation.
On average, it
is 3 – 5 times cheaper to save a watt of energy through conservation
than it is to generate that same watt of energy through solar
power. Conservation techniques include designing your home to take
advantage of passive solar
for both heating and natural light,
energy efficient appliances
such as Energy
Star certified, super
insulation
and high
efficiency windows
and
exterior doors,
and
compact fluorescent light bulbs
which are 4 – 5 times more efficient than incandescent bulbs. An
incandescent bulb is actually a heater that happens to produce a
little light – 90% of its energy consumption is lost to heat, only
10% is used for light. Compact fluorescents are also cheaper than
they’ve ever been and with warmer, more natural appearing light.
Typical costs
range from $7,500 - $10,000
per installed kilowatt.
The more kilowatts the system produces, the lower the cost per
kilowatt. This is because each system has common components.
Solar panels
which generate the power (about 60% - 70% of system cost), an
inverter
which converts the DC power produced by the solar panels to AC power
that can be used by your home and the utility grid, a
production meter that measures
your
gross energy production, one or more
safety shut off switches
which isolate your solar panels if they require maintenance,
wiring,
and
racking
for the solar panels. The larger the system, the more of the
overall cost can go to your solar panels and the lower price per
kilowatt you can achieve.
.jpg)
From left to
right: Utility revenue meter (pre-existing), safety shut off
(conduit going up leads to solar panels on the roof), a SunnyBoy
2100 watt inverter, the production meter with conduit going through
wall to the service panel inside. System located in Lake Crescent
area.
The
solar modules
we use carry 20 – 25 year
warranties
(depending upon the manufacturer). Most modules are warranted to
perform at 80% of their original manufactured power at the end of
the warranty period. What is their overall life expectancy? It is
hard to know. Solar panels constructed by Bell Labs in the 1950’s
are still working today, after over 50 years. The
SMA inverters
carry a
standard 5 year warranty plus an
additional 5 years
(for a total of 10 years) because Power Trip Energy’s installers are
licensed “solar pros” through SMA. We sell and install high quality
components so that we can sleep well at night. If you have a
problem with your system, we’ll be there to take care of it.
.
A recent study the National Renewable Energy Laboratory conclusively
demonstrates that energy payback for photovoltaics is, in the worst
case, less than 4 years. Given that PV module lifetimes are
generally in excess of 20 years, a PV system will produce far more
energy than it consumes over its lifetime. Technological progress in
the years since the issuance of this report has tended to bring down
the energy consumption of PV manufacturing yet further, as silicon
growth processes in particular become more efficient. For more
information about this and other “myths” of solar energy, please see
www.seia.org/mythsandfacts.php.
Solar grid-tied
pv systems have no moving parts and are nearly maintenance free.
The tempered glass surface of the panels naturally shed water (and
any accumulated dust) and are about as tough as a car’s windshield.
We mount the modules about 4 – 8 inches above the surface of your
roof so that stray branches or leaves will not be trapped under
them. With grid tied pv, there isn’t much to do except watch the
kilowatt hours of energy you’ve generated add up.
In the case of
a power interruption, the inverter is designed to immediately shut
down. This is a safety measure built in to ensure that during a
blackout your solar panels will not back-feed the grid and
potentially injure utility service personnel. If you are interested
in having a back-up power source in times of extended power outage,
we recommend you consider a small, efficient generator.
There are
several reasons we do not recommend batteries for back-up power.
The most economical batteries available today are flooded lead acid,
deep cycle batteries (think heavy duty car batteries each one about
the size of a five gallon gas can.) First, on a residential scale,
they and the additional equipment needed, are quite expensive.
Second, they require power management and regular maintenance
(checking and refilling water levels, unless you spend an extra
premium on gel or AGM batteries, and don’t even ask about NiCAD or
Lithium batteries). Third, they must be replaced periodically even
with the most diligent maintenance and care. Fourth, you will need
a large physical area to house 8 or 16 of these gas can-sized
batteries, which by the way are toxic and potentially dangerous.
Fifth, in time of a power outage, even with a massive battery bank,
you will be limited to the amount of power stored in your batteries
and the limited power your solar panels can put back into them.
Because power outages most often occur in the winter, when days are
short and skies are cloudy, this may not be very much power.
Convinced yet?
If you’re still
interested in back up batteries or an off-grid system, we are happy
to work with you. We just feel strongly that you need to know what
you are getting yourself into. But if it is the best solution for
your situation, we are glad to help.
12.
What are the environmental benefits of PV?
Solar electricity generated at your home or business is a
lot friendlier to the environment than the electricity from the
grid, which relies primarily on fossil fuels, nuclear, and massive
hydro projects. Fossil fuels contribute significantly to many of
the environmental problems we face today – greenhouse gases, air
pollution, and water and soil contamination – while renewable energy
sources contribute very little or no pollution.
The use of fossil fuels
has significantly increased greenhouse gas emissions creating an
enhanced greenhouse effect known as global warming. Renewable energy
technologies, however, can produce heat and electricity with a very
low or no amount of carbon dioxide emissions. Specifically, each
installed kilowatt of PV prevents 15 tons of CO2 over a 30 year
period compared to that same electricity generated from coal.
People often think of the electricity we use in Washington State as
being “green” because it is generated by hydropower. In actuality,
only a portion of our electricity comes from hydropower. By 2005,
over 55% of PSE’s power supply profile was coming from fossil
fuels. See the fuel mix from PSE’s web site @
http://www.pse.com/energyEnvironment/energysupply/Pages/EnergySupply-Electricity-PowerSupplyProfile.aspx
below:
.jpg)
* Wind power is expected to make up
about 5% of PSE’s power supply by the end of 2007.
Also, here in the NW, we
are especially aware of the damage done by hydro-power producing
dams, as they are the major factor in the devastation of one of our
most valuable resources, the native salmon runs. The loss of salmon
has decimated the NW fishing industry and has had significant
negative impacts to local Native American cultures.
13.
How
does renewable energy help our local economy?
In Washington, we rely heavily on energy produced from
natural gas and coal, both imported from out of state, to provide
electricity. The cost of these fossil fuels can add up to billions
of dollars. And every dollar spent on imported energy is a dollar
that our local economies lose. Renewable energy resources, however,
are developed locally. The dollars spent on energy stay at home,
creating more jobs and fostering economic growth.
Renewable energy
technologies are labor intensive. Jobs evolve directly from the
manufacture, design, installation, servicing, and marketing of
renewable energy products. Jobs even arise indirectly from
businesses that supply renewable energy companies with raw
materials, transportation, equipment, and professional services,
such as accounting and clerical services. In turn, the wages and
salaries generated from these jobs provide additional income in the
local economy. Renewable energy companies also contribute more tax
revenue locally than conventional energy sources.
14.
What
happens when I call Power Trip Energy? What steps will you go
through to evaluate my home or business?
When you call our office we’ll answer your questions about grid-tied
solar pv. If you are interested in having your home or business
evaluated for a solar pv system, we can schedule a
site evaluation.
During a site
evaluation, we will come to your home or business (or vacant lot if
your planning to build) and we will evaluate the solar potential of
your site. We’ll climb on the roof of your house and take the
measurements necessary to design your system. We’ll use a
solar pathfinder
to accurately assess any the orientation and solar potential of your
roof or ground mount site. We’ll look at your home’s electrical
system to determine how we will connect your solar panels to your
service panel and the utility grid. Finally, we’ll sit down with
you so you can share your goals regarding generating your own green
power. We’ll answer all your questions about costs, financial
incentives, location options, various system sizes, maintenance
(there really is none), and whatever else you can throw at us.
Within a few days of the site evaluation we’ll send you a written
bid for one or more pv systems and an installation contract. The
cost for a site evaluation
on the north Olympic and Kitsap Peninsulas within 50 miles of Port
Townsend is $150. We charge a little more for site evaluations
beyond 50 miles to cover our time and travel cost. If you purchase
a pv system through us, we’ll credit this amount to your purchase
price.
Great! When
you are ready to commit to buying a system, we’ll ask you to initial
the system bid you are accepting, sign the installation contract,
and send us a deposit that equals one-half the cost of the materials
and the shipping. We will then order the solar modules and other
equipment. When the materials arrive (2 – 6 weeks depending upon
availability) we’ll schedule their installation with you. When we
deliver the materials to the site you’ll pay us the other one-half
of the material and shipping costs and we’ll begin to install the
system. System installation typically takes 3 – 6 working days.
Once the system is installed and passes the electrical inspection
you’ll make the final payment which covers the installation. The
cost of the electrical permit is included in the bid and we’ll take
care of the permit and the various rebate and sales tax exemption
forms. We’ll make it easy for you to invest in solar power and
create your personal energy policy.
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