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The cow waste produces 250 to 300 kilowatts of electricity daily, enough to power 300 to 350 homes, according to the utility.

1. Pro 1 kW heat = 0.4 - 0.9 m³ storage space - depending on the house Dämmzustand
(inkl. Leerraum) (including space)
2. Nutzbarer Lagerraum = 2/3 Lagerraum (inkl. Leerraum) Effective storage space = 2 / 3 storage space (including space)
3. 1 mł Pelletsmenge = 650 kg 1 m³ pellets quantity = 650 kg
4. Energieinhalt = ca. 5 kWh / kg = Energy content of about 5 kWh / kg

Beispiel: Example:

Einfamilienhaus mit einer Heizlast von 15 kW Single with a heat load of 15 kW


= =


5.800 kg Pellets Jahresbedarf 5,800 kg pellets annual requirement

15 kW Heizlast x 0,9 mł / kW 15 kW heat x 0.9 m³ / kW


= =


13,5 mł Lagerraumvolumen (inkl. Leerraum) 13.5 m³ volume storage space (including space)

Nutzbarer Rauminhalt Effective capacity


= =


13,5 mł x 2/3 = 9 mł 13.5 m³ x 2 / 3 = 9 m³

Lagerraumgröße Storage room size


= =


13,5 mł : 2,4 m (Raumhöhe) = 5,6 m˛ Lagerraumfläche 13.5 m³: 2.4 m (room height) = 5.6 m ˛ storage space
(2,0 x 3,0 Meter sollte jedoch nicht unterschritten werden) (2.0 x 3.0 metres should not fall below)

Gelagerte Energiemenge Stored amount of energy


= =


5850 kg x 5 kWh / kg = 29250 kWh 5850 kg x 5 kWh / kg = 29250 kWh
(entspricht einer Heizölmenge von ca. 3000 Liter) (equivalent to a quantity of fuel oil about 3000 liters)

from the oil drum
back-of-the-envelope calculations
Kyle Schuant
the energy E required to compress air at 25C is,

E = 110,000 x ln (P1/P2) /m3/mol

There are about 45mol air in 1m3, so,

E = 110,000 x ln (P1/P2) /m3

This howstuffworks article tells us that an air car tank might have 300lt at 4,561psi, which is 29,999,087.707 - call it 30,000 kPa. Atmospheric pressure is 101.3kPa. 300lt at 30,000kPa will be 90,000lt at atmospheric pressure, or 90m3. And so we get,

E = 110,000 x ln (30,000 / 101.3) x 90
= 110,000 x 5.69 x 90
= 56,331,000J
which is 15.6kWhr

However, a company which supplies air compressors tells us that "Most systems typically waste 25 to 50 percent of the energy required to generate compressed air that actually provides useful work."

Let's be optimistic and assume that with lots of air cars zooming around, service stations will buy the most efficient (expensive) compressors. So we get just a 25% loss. This brings us to 20.9kWhr.

Let's round it up to 21kWhr to refill the tank. Again, this isn't the air car referred to in the article, but it gives us an idea of the order of magnitude.

21kWhr to travel 200km.

A regular small city car gets about 10km/lt. Petrol costs about $1.30/lt, and causes 2.32kg CO2e/lt. So to go 200km in a regular car would cost $26 and cause 46.4kg CO2e in emissions.

Electricity from coal cost $0.1355/kWh and 1.21kg CO2e/kWh, so the 200km journey would cost $2.85 and cause 34.9kg CO2e in emissions.

Electricity from wind costs $0.19/kWh and causes 0.04kg CO2e/kWh. So the 200km journey would cost $3.99 and cause 0.84kg CO2e in emissions.

The average Australian car is driven 15,000km annually. That'd be 75 refills, or 1,575kWh energy in all. That's not bad when the average household uses 6,000kWhr annually.

A development of homes in Kissimmee do a better job at utilizing solar energy than a dozen other neighborhoods in the Southeast and they got an award for it.

The 2007 Aurora Awards Committee gave Rey Homes' Villa Sol development an award called the ""Best Solar Energy Home.""It definitely works," Hassan said.

After living in his new home for only three months, Hassan said he is already saving money because of something that looks like a skylight.

But it is not a skylight. It is a solar panel that is used to give him hot water.

When Hassan wants hot water, he gets it. In fact, he says a solar hot water system works better than the standard one did. But, Hassan said, that isn't even the best part.

"You're saving money on your bill, but you actually have a bigger house," Hassan said.

AllSolar Service Company is teaming up with Rey Homes to build Villa Sol. They said a home with a solar hot water system will save you between 15 and 30 percent each month.

"So that allows you to have anywhere from $50 to $100 extra a month," said Aldo Martin, of Rey Homes.

OK, the numbers: suppose you use 1000 gallons of oil to heat your home (that’s how most of us heat here in the Northeast despite the fact that we don’t like refineries). At $3.00/gallon (my guess for next winter), that costs $3000 (duh). According to my favorite government spreadsheet, there are 138,690 BTUs in each gallon of No. 2 fuel oil so you’re buying about 140 million BTUs to keep you warm. However, because even a good furnace is only 78% efficient, only 108 million of those BTUs do you any good.

If you were to create all the useful BTUs with conventional electric heat, you’d need to buy about 32,000 kilowatt-hours (3412 BTUs per kWh). At the $.16/kWh we’ll be paying here next winter, that’s $5000 dollars. Stick with oil!

But, according to the same spreadsheet, geothermal is 3.3 times as efficient as conventional heat (because you’re just pumping up what you need). With geothermal you’ll need less than 10,000 kWhs and pay about $1500; you save 50% compared to oil!

According to Excel, the present value of $1500 per year over 20 years at 6.5% interest (actually your heat pump system should last longer) is a little more than $16,000. If you can get a heat pump system with the capacity you need installed for that amount or less, you’ve got yourself a bargain – no subsidies involved. Actually, if it’s a new installation then you have to take into account what a furnace and fuel tanks would have cost as well. Distributing the heat inside the house is best done with circulating water but can be done with hot air as well. Either you already have a system to do that or you’d need to pay for one anyway. You can also get your domestic hot water from the heat pump and save a little more. If the price of oil goes up faster than electricity, you save more – and vice versa.

Can you get geothermal heat with this capacity installed for this amount? Depends. It depends on whether you have land that’s easily dug down into, a well, or a pond. If your ho

Windows-based PCs have long partitioned disks using the Master Boot Record (MBR) disk partitioning scheme. MBR is popular because it has been around for a long time and is compatible with many operating systems. It is also very limiting, however, especially given the capacity of modern hard drives.

Newer operating systems such as Windows XP x64, Windows Server 2003 (64-bit), Windows Vista (both 32- and 64-bit editions), and Intel-based Mac OS X support the GUID Partition Table (GPT) disk partitioning scheme. GPT is a modern, flexible, and forward-looking disk partitioning schema. GPT Mounter was created to give Windows XP and Windows 2000 access to volumes on GPT-partitioned disks created using these newer versions of Windows.

GPT Mounter Limitations

Neither Windows XP nor Windows 2000 are capable of properly formatting volumes on GPT-partitioned disks. Though GPT Mounter does what it can to protect against damage if this is attempted, it should be avoided, and should not be expected to work. If you need to reformat a volume on a GPT-partitioned disk, you should use the operating system that created the disk.

GPT Mounter does not enable Windows to read foreign file systems. Though GPT Mounter will work with a disk GPT-partitioned using Mac OS X or Linux, you are only able to mount volumes created using a file system Windows understands, such as FAT16, FAT32 or NTFS. Windows doesn't natively understand Linux ext2, ext3 or ext4 volumes, nor does it natively understand Mac HFS or HFS+ volumes.

If you want to mount HFS and HFS+ volumes under Windows, you need MacDrive.