We know, there’s no shortage of ways to waste time on the computer, and we’re not trying to get you in trouble with your boss–but before you get back to work, take a look at three useful tools for folks who are concerned about climate change:
Have you calculated your carbon footprint lately?
The CoolClimate carbon calculator covers it all–transportation, energy, even the food you eat and the stuff you buy. Be sure to check out the feature that lets you compare yourself (or your small business) to other households or businesses–but remember, even if you have the smallest footprint of any American, you’re still generating tons more carbon than most people in the world, so don’t skip the “Take Action” link.
The Good Widget
After calculating your carbon footprint, you might feel a bit despondent, so here’s something to renew your optimism. The widget below, courtesy of the Carbon War Room, shows the number of solar watts being installed in the US. Relax and enjoy the lovely vision of the flickering, ever-rising number.
The Wicked Widget of the West
Last but not least, prepare to get depressed again when you check out the Atmospheric CO2 widget which, like the solar widget, is endlessly ticking upwards. And on that note…use the tools, share them with your friends and turn off your computer when you’re done.
Solar energy is dependent on… the sun! Who would have guessed!? As solar studs, I think it’s pretty important for all of us to have (at least) a basic understanding of the star that unequivocally is the reason there is life on earth.
First, a little history; About 4.5 billion years ago, gas and dust coalesced and formed what turned into our solar system (you know, the sun, eight planets, one newly minted dwarf planet named Pluto and other comets and asteroids). Our Sun makes up 99% of the mass in our solar system.
Despite the importance we hold for our sun, it turns out that our personal star is one of over a 100 billion in the Milky Way Galaxy and happens to be pretty average in size. This is a good thing, because stars with a higher mass burn out after a few million years (a blink of an eye when discussing the cosmos). Our sun, on the other hand, is calculated to burn for another 4,500 million years.
The way the sun functions is pretty awesome. It’s essentially a giant nuclear reactor. At its super dense core, hydrogen atoms fuse to create helium at the incredible rate of 700 tons per second. This reaction creates energy. The energy is carried from the core to the surface of the sun with photons-particles of light. It takes the photons more than a million years to migrate from the core to the surface of the sun. The photons then travel down to us at earth.
The sun is about 10,000 degrees Fahrenheit on the surface and 28 million degrees Fahrenheit at its core. Think about that the next time you complain about your summer heat!
At last, what every wannabe solar homeowner in California has been waiting for…on Feburary 26, the humble net metering cap was raised from 2.5% to 5%. Net metering allows solar power generators to get some financial benefit when they generate more power than they use rather than making an involuntary gift of free electricity to their utility company.
Here’s how net metering works: When your solar panels generate power, that power is sucked into the giant power grid that serves your area. If, at the end of the year, you have consumed less electricity than you fed into the grid, then you’re entitled to an offset on your electric bill. Seems only fair, right?
Until last week, utilities only had to offer customers the excess power generation credit until the point at which the utility’s was meeting 2.5% of its peak load with solar power generated by its customers (at which point they could turn customers away from the program). Now, utilities will have to keep paying out the credit until they’re getting 5% of their electricity from solar (which isn’t going to happen for several years). This means lots of new room in the net metering program for tens of thousands of homeowners, schools, municipalities and businesses that install solar systems in the years ahead.
Did you know that the optimal solar weather isn’t a bright cloudless day? In fact, sunny days that are partially cloudy are the best days. This is because as the radiation from the sun travels through the atmosphere, it is reduced by absorption, reflection and scattering. But, reflected radiation from sunlight bouncing off clouds (called diffuse radiation) can increase the irradiance-the amount of electromagnetic energy on a surface per unit time per unit area-that eventually hits the surface of the earth.
With public school budgets being cut to the bone, this may seem like an unlikely time for school districts to start installing solar PV systems. But a number of new incentives make this the ideal time for schools to solarize.
The California Department of Education estimates that school districts spend $132 per student per year on energy-that means our nearly bankrupt state is spending $700 million a year burning fossil fuels.
More than 35 schools in California have gone solar, including Berkeley’s own Washington Elementary. Most participated in the California Solar Schools Program, which is now closed, but a handful have begun to take advantage of new incentives and attractive financing mechanisms, such as PPAs (Power Purchase Agreements) that allow the school district to pay the system off over time.
If you’d like to help your kid’s school save money and the planet, the Helios Project has all the tools you need to get started. Independent schools, unfortunately, are not eligible for many of the incentives available to public schools, but still may be able to find a commercial installer who will offer a PPA or a lender who can loan the money at a favorable enough interest rate that the school will still save money in the long run.
The California Energy Commission also has some other tips for how schools can save money by conserving energy, including turning out lights in empty classrooms, turning down the thermostat and fixing leaky hot water faucets. And be sure to check out the free solar curricular resources offered by the SunPower Foundation.
Energy, and electricity in particular, has several different units of measurement that can be more than a little difficult to understand, but I’m going to go ahead and try.
First up is the British Thermal Unit (BTU). The BTU is a measure of heat energy (not electricity). One BTU equals 252 calories, and will raise one pound of water one degree Fahrenheit. It is about equal to a match or a burning candle. One barrel of fuel oil (42 gallons) offers 140,000 BTUs of energy. To produce one million BTUs you would need one of the following:
80 lbs of coal
250 lbs of hardwood
11 gallons of propane
7 gallons of #2 diesel fuel oil
293 Kilowatts of electricity (more on this below)
BTUs are generally measured in quads (one quadrillion BTUs). The world uses about 400 quads a year and the United States uses about a quarter of that, or 100 quads.
Electricity has three basic units of measurement; voltage-measured in volts; current-measured in amps; and, resistance-measured in ohms. A good way to understand these units is to think of a hose. The voltage is equivalent to the water pressure; the current is equivalent to the flow rate; and the resistance can be compared to the hose diameter.
Power is the rate at which energy is generated and consumed and is measured in watts. Watts are the product of volts and amps. 1000 watts is one kilowatt, and 1 million watts is a megawatt. California currently has 500 megawatts of solar power, spread over 50,000 solar participants.
A watt-hour is equal to the work done by one watt acting for one hour. For example, a 100 W light bulb that is on for one hour uses 100 watt-hours (or .1 kilowatt hours). Your energy utility measures your use in kilowatt-hours.
One last term that is useful to know is “load.” A “load” is anything on the electrical circuit that draws power. Your refrigerator, TV, and electric toothbrush are all examples of loads. And the fact is, we have just gone over a “load” of information!
The bill (S. 3224), sponsored by Senator Bernie Sanders (I-VT), would provide $2-3 billion worth of rebates to residential and commercial property owners who install solar PV or solar hot water heaters. The rebate would offset up to half the cost of installing a PV system. Once implemented, the 30,000 megawatts generated by these systems would be the equivalent of 30 nuclear power plants.
Turn up the volume on why we need 10 million solar roofs pronto.
Sitting in the office of a solar company, I hear words such as volts, watts, kilowatts and kilowatt-hours tossed about with abandon. With my non-technical background it sounds like what I imagine a European must hear when Americans discuss a baseball game - it’s certainly a little confusing. To combat this confusion I compiled some questions I have such as, where does our energy come from, and where does it go? As well as, how is it measured? With these questions in mind I did some research so that you readers wouldn’t have to. My plan is to spend the next couple of posts addressing these issues.
This first post is going to cover some pretty big picture stuff.
The energy in the United States doesn’t go solely to powering our homes. In fact, it’s a pretty inefficient system. (source, The Idiot’s Guide to Solar Power for Your Home):
25% goes for transportation
20% is used by industry
12% is for homes and businesses
AND 40% of energy in the US goes to making electricity
According to the Department of Energy, in the average home which spends about $1200 a year on their utilities, energy use can be broken down in the following way:
43% goes to heating and cooling
29% goes to lighting, cooking and appliances
12% goes to water heating
8% goes to refrigeration
8% other
These are just some interesting facts to mull over. Keep your eyes open from some more in the next few days.
At this year’s TED conference, Bill Gates issued a clarion call for “energy miracles” that will bring global carbon emissions down to zero. Gates’ philanthropic focus has been on education, vaccines and malaria but, in his 2010 TED speech, he said that his one wish for the next fifty years is not to pick the next President nor to discover a silver bullet vaccine–it is the global deployment of zero-emissions energy technology at half the current price.
Reflect for a moment on how earth-shattering (or, should I say, “earth-saving”) Gates’ epiphany could be: Here’s one of the wealthiest and most influential individuals on the planet asserting what we climate freaks have been trying to communicate for the past decade–that if we want to have a life-sustaining planet, we can and must get to zero. And when Bill Gates talks, people with money listen.
Gates begins the talk with a simple math equation even I was able to understand: Global CO2 levels = # of people on the planet x services people use (eg. electricity, food) x energy required per service x CO2 per unit of energy. As you might recall from 4th grade, if the product of an equation is zero, at least one of the factors being multiplied must be zero. Of all the factors, the only one that could conceivably be reduced to zero is the amount of CO2 per unit of energy. To do so will require major advances in the scale and reliability of five energy technologies–solar PV, solar thermal, wind, nuclear and carbon capture. Gates believes we must work intensively on all five fronts by investing heavily in research & development and creating market incentives to move away from fossil fuels.
We couldn’t agree more (with respect to the first three energy technologies on Gates’ list). Dubious and unsafe technologies aside, we applaud Gates for embracing the gravity of our energy predicament and using his platform to inspire innovation.
The Ecology Center and the City of Berkeley have teamed up to put on a workshop on How to Reduce Your Carbon Footprint in 2010. The workshop will be held on February 25 from 7-9 pm at the Unitarian-Universalist Church at 1924 Cedar St. in Berkeley. You’ll learn how to reduce your own footprint and local resources available to help your friends and neighbors get on board. Can’t make it? Don’t fret–check the Ecology Center calendar for future workshops.