Editor’s note: Don’t miss the Whole Earth and Watershed Festival from 10 a.m. to 3 p.m. Saturday. Get more details from writer Paul Shigley and read his piece on Shasta College’s sustainability conference.
Energy is great stuff, and in Northern California we use a lot of it to get around, power our homes, and produce the goods and services that make up our economy. Many people think of energy efficiency and renewable energy as expensive. In fact, they can save you money. The purpose of this guide is to help you decide what kind of energy to use to get the most power for your dollar, and to use it to more efficiently to produce the least CO2 pollution, to reduce your “carbon footprint.”
Of course, there are other environmental effects to energy use, besides CO2 pollution. Some of the types of electricity production which have the smallest CO2 emissions, such as hydroelectric and nuclear power, have other, very serious, adverse environmental consequences, that must also be taken into account. But for many people, the cost of energy is the first consideration. And C02 pollution levels can be hard to get a handle on. So those are the factors that this guide focuses on, and will help you to calculate.
Before we go further, let’s state the obvious. The cheapest energy you will ever buy is one you don’t. Conservation is the first principle, both in saving money on energy and reducing the adverse environmental effects of energy use. But, if you intend to live “on the grid” and plan to drive a vehicle, you will need to make choices in the type of energy you buy, and the way you use it.
As you read on, you probably will see that you use both primary and secondary fuels. Hydrocarbon fuels derived from fossil deposits, such as gasoline, diesel fuel, propane and natural gas, are such primary fuels, which you burn directly in your vehicles or home appliances. Electricity is a secondary fuel, produced by converting other forms of energy to the very versatile “juice.”
For many home uses, grid electricity is the only practical alternative. But for some uses, electricity has a high price. You’ve probably heard of fuel cells, which may well be game changers for efficient electricity production in the future. But for now, your utility burns fossil fuels to create mechanical energy, then converts that energy to electricity. The process has improved quite a bit since Thomas Edison first did it about 130 years ago, but it still has poor energy conversion efficiency. Only about 40% of the energy contained in the fossil fuel, typically natural gas or coal, makes it through the power line to your home. The other 60% still has to be paid for – by you – in your electric bill. And despite some renewable and nuclear energy content, fossil fuels produce most grid electricity. So, your electric appliances are actually getting their heat (largely) from natural gas, but they are doing it indirectly, inefficiently, and expensively.
To save money, and reduce your carbon footprint, it’s usually beneficial to reduce your grid electricity use wherever possible, both by conservation, and replacing electricity with renewable and conventional primary fuels. The chart at this interactive link, builditsolar.com/References/Calculators/Fuels/FuelCompare.htm, will help you to find your savings. It translates different types of energy measurements to common values, what it costs (the prices printed here approximate Spring 2010 local prices) and how much C02 pollution is created.
You can go online, enter the unit costs from your own energy bills, the efficiency ratings of your appliances (the default values are typical) and see exactly what savings another fuel may offer you. Be sure to also check out the links at the site for more excellent energy information and advice. A kilowatt hour (KWH) is 1000 watts consumed for 1 hour. Another way to think about this is that it’s enough electricity to run a 100-watt lightbulb for 10 hours. Natural gas is measured on your bill in therms. As you can see, (PG&E) natural gas prices are relatively low right now, but remember that, unlike electricity, they change month-to-month. If you heat with wood, you probably already know that a cord is 128 cubic feet. The calculator translates the different fuels into cost in dollars, and CO2 emissions per 100K BTU of heat, in the two columns to the right.
Many home energy uses require electricity. But if you need energy to produce heat, you’re almost always better off using primary fuels, rather than electricity, even though prices are often lower for electric appliances. Large cost and CO2 pollution savings can be had by replacing electric resistance heating appliances, which may account for a very large percentage of your electric bill, with natural gas or propane.
Electric water heaters (except for heat pumps), clothes dryers, stoves, and space heaters are among the biggest money pits. Look at it this way. It takes 100 BTUs of natural gas to get the heat your utility converts to electricity, to get you about 40 BTUs of electric heat for your hot shower. This is the main reason you can cut your energy cost and CO2 pollution by half, or even more, by switching from electricity to gas. As you can see, propane gives almost the same CO2 savings, but tends to be higher priced than natural gas.
You can reduce your energy bills even more significantly by using renewable energy. When many people think of “renewables,” they think of huge wind, solar, biomass, or geothermal projects at the other end of a power line, or of photovoltaic solar rooftop installations. But in fact, many North California residents use “renewables,” solar, biomass, and geothermal energy, as primary home fuels.
Passive solar is simply orienting your home to take advantage of sunlight to heat your home in winter, and to avoid unwanted solar heating in the summer. You can tune your home’s passive solar heating by adding or removing shade, as required. Deciduous trees shading windows can make a significant cut in your summer AC costs. Consider solar water heating, often the most cost-effective home renewable energy improvement you can make, thanks to our sunny climate. Home biomass means wood or pellet stoves and inserts. You can usually buy these local renewable fuels at prices lower than fossil fuels. Get an EPA-approved stove and learn to use it correctly to produce the least smoke possible. Northern California pioneers used geothermal resources as a source of cooling, by using caves and cellars to store perishables. You can get big savings on heating and cooling by using the geothermal resources under your home by installing a geothermal heat pump, to both cool and heat your home, and even heat your water.
A note on heat pumps. Air conditioners and refrigerators are heat pumps, used for cooling. They can also work in reverse, in heat mode. Instead of pumping the heat out of your house (through that big noisy box by the side of your house or on your roof), when you use the AC, they work in reverse and pump outside heat into your home, in order to heat it. Since you aren’t converting energy to heat, just using energy to move the heat around, you actually can get more than 100% efficiency. Note that the chart default value is 220% efficiency. But in fact, efficiency is a function of what temperature your outside air is. As it gets hotter outside, your AC loses efficiency, and as it gets colder outside, your heat function does also. So, most home AC/heat pumps don’t work as well when you need them most.
This is where a Geothermal Heat Pump (GHP), while more expensive to install, can dramatically improve your home’s energy efficiency and heating and cooling operating costs. Essentially, a GHP takes the heat out of your home in the summer and “buries” it under your home in the summer. It then “digs up” that same heat for you to use to warm your home in the winter. The ground a few feet under your house (unlike the air) is about 60 degrees Fahrenheit year round, so efficiencies of GHPs are very high, often in the 300-400% range.
Local utilities charge you about the 12 cents per kilowatt hour “base” rate shown in the chart, though PG&E charges a lot more if you use enough electricity to get into the higher charge “tiers,” and local public power companies charge you a “service fee,” in addition to your electricity (KWH) charge. Take a look at your bill for your exact costs. But, as you can see from the chart, pretty much any type of primary fuel is cheaper than even the low “base” rates for electricity, and also produces less CO2 pollution.
The chart shows CO2 emission rates for the national grid. You can go to the “content label” page of your utility’s website, and see how they compare to national norms. Generally, California utilities produce less CO2 per unit of power (KWH) than the national average, because they use less coal, the most CO2 polluting fossil fuel, and more low carbon renewables, such as hydroelectric, wind, and solar power generation.
When most Northern Californians calculate their total energy use and “carbon footprint,” the total CO2 pollution they produce, vehicle use is often responsible for the largest share. This is because vehicles require a lot of energy, and use it inefficiently. Of course, driving a high-mileage vehicle, whether gasoline, diesel, or hybrid, and simply driving less, will reduce your CO2 pollution.
Gasoline and diesel have been the primary vehicle fuels for the last century. High energy density means they are excellent energy storage mediums, allowing for low fuel weight and a long range between fill-ups. Unfortunately, each pound of fuel burned produces about three pounds of CO2 pollution. Another way of looking at this is that each gallon of gasoline burned produces about 1,300 gallons of CO2 pollution. So, if you, like many folks locally, drive a vehicle that gets 20 mpg and you drive 20,000 miles a year (and buy 1000 gallons of gas at $3/gallon) you are spending $3,000 a year on gas and are producing 1.3 million gallons of CO2 pollution each year. Ouch. Well, maybe you don’t want to ride a bike, or even drive a hybrid. But there are now many large vehicles that average 30 MPG, or better. By driving one, and reducing your miles driven to 15,000 a year, you can cut by half both your gasoline costs and your vehicle’s CO2 emissions.
Another option will soon be available – Electric Vehicles (EVs). We’re stretching the 2010 date a bit here. Several practical (with ranges of 100 miles or more and prices of $35,000 and less) electric vehicles will hit the market within a year, but we may have to wait a little longer to get the fast-charging infrastructure to “fill-up”on the road here in North California. But you can start thinking, and planning, now.
EVs will allow drivers to cut both fuel use and CO2 pollution dramatically. Yes, I know I just told you to cut grid electricity use. But internal combustion engines, like the one in your vehicle, are so inefficient, they are the major exception to this rule. Remember that the conversion of primary fuels to heat by burning, such as in a natural gas water heater, is quite efficient. In contrast, converting the same natural gas (or gas or diesel) fuel to mechanical energy, in an internal combustion engine, is probably your best use of energy having the lowest energy conversion efficiency. Look under the hood of your car, and you’ll see the entire cooling system, including the radiator, water pump and fan are just there to dump the waste heat (and that’s the same energy that you just paid for at the pump!) out of your engine. Estimates of internal combustion engine energy conversion efficiency are in the 20% range – about half that of a fossil-fueled electric power plant.
Another way of looking at this is that by moving the primary fuel consumption from your car’s engine to your utility’s (about twice as efficient) power plant, you can just about double your miles-per-fossil-fuel gallon, and halve the CO2 emissions per mile. You are also replacing imported oil with domestically produced fuel, the less-polluting natural gas. Costs should be far lower also, since many utilities give an off-peak rate. PG&E currently offers an optional time-of-use rate that charges 5 to 6.4 cents a KWH to EV owners who charge up their cars at night. That works out to as low as $1.25 for a 25 KWH “full charge,” good for up to 100 miles. Annually, that adds up to about $200 in electricity for 15,000 miles of EV driving, as opposed to $1,500 for the same 15,000 miles driven in a 30-mpg gas vehicle, at $3 per gallon. A comprehensive look at alternate fuel vehicles can be found on the links at the electric vehicle page:
So, you drive a gas-guzzler, and you have an all-electric home?
And you are going broke paying the bills?
You’re not alone.
When gas and electricity were cheaper, and the environmental threat of C02 pollution was unproven, this may not have seemed like such a bad idea. But today, you can do much better.
Sit down and figure out what holding on to your antiques is costing you in 2010 dollars, and costing the planet in CO2 pollution. Use the online calculator to see which improvements give you the most bang for the buck. The entire nation is trying to improve efficiency, cut down on C02 pollution, and reduce America’s dependence on imported oil. Many Federal, State, and local programs are available to help pay for efficiency upgrades. See if they will make your home or vehicle energy efficiency improvements even more affordable.
Think. Act. Save.
Ed Marek developed an interest in rational energy use, utility management and energy policy, as a result of more than 30 years of paying PG&E bills, and a three-month experience last year defending his home in Shasta County from REU’s (TANC) Power Line to Nowhere. His passive solar home had a total non-renewable energy bill last year of about $380 for grid electricity, and $170 for propane. He’s now (fairly seriously) looking at electric vehicles.