Archive for February, 2009

With an election looming in Queensland, the state of the economy and the subsequent job loses have been high on the agendas of both major political parties. Very little has been said about the renewable energy industry and its ability to contribute to not only greenhouse-gas reduction, but to job creation as well.

Focusing on household energy efficiency, solar hot water and increasing solar power generation will not only create jobs — it will also help Queenslanders save money in a tough economic climate. But once again it has been left to the minor parties to suggest these smarter solutions.

Australian Greens Leader Bob Brown and Greens MP Ronan Lee recently launched a plan to create more than 7600 green-collar jobs in Queensland.

“The Greens will create thousands of green-collar jobs in Queensland by retrofitting homes for energy efficiency and investing in clean energy infrastructure,” Senator Brown said.

“Unlike President Obama, who has committed to creating 5 million green-collar jobs, the state and federal Labor governments are spending taxpayers’ money to support big banks, big polluters and big developers.

“The Greens EASI-Q program will retrofit Queensland homes with better insulation and solar hot-water tanks, reducing power bills for ordinary Australians and creating 3,200 jobs by its fifth year of operation,” Senator Brown said.

Greens MP Ronan Lee said the Labor and Liberal parties were locked into an old approach to job creation.

“There’s not a single environmentalist or renewable energy expert on the Premier’s so-called Jobs Squad,” Mr Lee said.

“The Greens want to see Queensland develop an economic base that continues to create jobs into the 21st century. That’s why the Greens would invest in two 250 megawatt solar power stations for Townsville and the Darling Downs,” Mr Lee said.

The solar power stations will cost a total of $4 billion, with State and Federal Governments underpinning half the cost. The development of the clean energy infrastructure will create 4,000 jobs in the construction phase with 400 ongoing jobs.

Sustainability organisations are concerned the upcoming Solar Credits Scheme will damage the future of Australia’s small-scale renewable energy generation.

In a joint statement from the Alternative Technology Association (ATA), Greenpeace and the Moreland Energy Foundation, they said it is imperative the federal government stops its inconsistent and confusing solar power policies, or risk Australia’s solar future.

The statement, submitted to the Department of Climate Change draft Renewable Energy Target (RET) legislation committee, said the government’s new Solar Credits Scheme will actually reverse the impact of installing household solar systems.

“Households investing in solar do so at significant personal cost. In return for their sacrifice, the government is effectively cancelling out the greenness of their solar system,” said Damien Moyse, Energy Advocate for the ATA.

Government figures show the amount of renewable energy installed in Australia is significantly increasing.  According to a recent survey by the ATA, there are two main motivators for this growing trend. To reduce emissions associated with electricity consumption and to increase the amount of renewable energy around the country.

Under the Solar Credits Scheme, due to start in July this year, homes installing solar panels will be supplied with five Renewable Energy Certificates (RECs) for every megawatt-hour of clean energy their system produces, instead of the usual one REC per megawatt-hour.

“Supplying extra RECs to solar homes means four out of the five RECs will be phantom and not represent real clean energy generation,” Mr Moyse said.

RECs are the trading currency for renewable energy. One REC is equal to one megawatt-hour of clean energy generation.

In order to recoup up to $7500 of the upfront cost of their system, solar homes will have to sell the extra RECs to large energy consumers or electricity retailers.

Mr Moyse said the new scheme will effectively nullify their climate-friendly solar electricity generation.

“These phantom RECs will be helping electricity retailers achieve their Renewable Energy Targets (RET) on paper, but not in real renewable electricity generation.”

Under the RET, electricity retailers are required to purchase 20% of their electricity from renewable sources by 2020.

The groups are calling for the federal government to put a stop to ineffective solar policies and fulfill its election commitment to consider the introduction of a strong feed-in tariff for small-scale renewables.

“The latest evidence suggests that climate change is happening faster than predicted and the burning of coal is at the core of the problem,” Mr Moyse said.

“A national gross feed-in tariff, like the one adopted by the ACT, will be a positive and decisive step to securing the future for small-scale renewable energy.”

Measuring Power and suggestions on becoming energy efficient

Part 1 and Part 2 looked at the basics of power. Using water as an analogy we discussed how taps and shower roses are the water-based equivalent of electrical appliances and lights. Restricting high rates of water flow, saves water. Restricting the use of high current electrical appliances, saves power. A leaking tap is similar to leaving an appliance on in standby mode.

In the final part of the energy efficiency series we’ll take a look at better ways of measuring your power consumption and some tips on being smart with your electricity.

As we briefly touched on in Part 1, the standard way of measuring power is the kilowatt-hour meter. Total power consumed is recorded on an ongoing basis. But there is no way to see what each appliance is using — which ones draw the biggest current and therefore consume the most power in the quickest time. How much power is consumed by leaving your TV, DVD, microwave and other appliances on, in standby?

Wireless Energy Monitoring

The Queensland Government’s Climate Smart Home Service is currently offering a wireless energy monitor. Most of us by now would have seen the ads of TV. After an electrician wires a link into your normal tariff meter (power and lights), you can use the wireless monitor to see what is known as real-time energy use. Real time because you can see the power usage instantaneously.

Turn your electric stove top on and you will see exactly how much energy it uses. Most people would be shocked at the amount of power a hot plate can use (this can be up to 7000 watts if all hot plates are turned on). Programming the cost per kilowatt-hour into the device (for example 15 cents per kilowatt-hour) and you can also see how much money you’re spending to make that next stir fry.

The benefit of using this device is simple. You can now witness the power consumption of each appliance, and even your lights. You can see how much power is consumed over night when you leave appliances switched on at the power point and left in standby mode. Walk around your kitchen or lounge room of a night with the lights off and notice all the small red or green lights and clocks still running on your appliances. They are like leaking taps.

The only power you can’t see is hot water systems’ and other devices like pool pumps that are connected to off-peak tariffs. Or, if you have three-phase power, you can only monitor one phase.

Lord Kelvin, of thermodynamics and absolute temperature fame, famously said: “If you can not measure it, you can not improve it.” This is very true when we consider the efficiency of the energy-hungry modern household.

Google enters the energy market

Google recently announced a project, the Google PowerMeter, where they are proposing to use the internet to monitor your energy use. This will require new, so-called smart meters which can communicate, in real time, your energy usage and then display this online. Issues exist around privacy and whether energy companies will use this information to introduce varying pricing structures. Technically, there are issues involving the high-speed internet connection required to gather this information.

Currently in Australia ‘smart meters’ or meters that can do more than just measure your power, are being used to turn different tariffs on (hot water and pool pumps) and measure grid-connect solar power generation. More advanced metering could potentially control high-current devices such as air-conditioners, notify authorities of power outages and monitor the amount and type of appliances in a house.

Tips to save power and reduce greenhouse-gas emissions

• The main tip — be informed. Everything we do creates an impact. But it is better to be informed so we are aware of what we’re doing.

• Take advantage of the Climate Smart Home Service — it’s cost effective. Monitoring your real-time energy use can save between 5 and 15 per cent of your power bill each month. Monitor your energy and find out the highest power consuming appliances. Treat power like water and use it sparingly.

• Switch off appliances at the power point. Do not leave appliances in standby mode. They are like leaking taps. If building or renovating, don’t place power points in the standard hidden areas at about 30 cm off the ground. Place them in positions where you can easily get to the switch.

• Consider the power consumption of appliances you are about to buy. Do I really need a big-screen plasma TV? They are big energy consumers –stand near one in a shop and feel the heat. Heat from an appliance is wasted energy.

• Install ceiling fans instead of air-conditioners. People still survived during summer prior to air-conditioners gaining popularity. Efficient ceiling fans can use 70 watts of power compared to big air-conditioners, which can use over 4000 watts. Moving air around your house and creating good ventilation is far more cost effective.

• Insulate your ceiling. Repel heat, before it gets into your house.

• Consider gas stove tops. Burning gas to heat a kettle is far more efficient then burning coal to turn a turbine, to generate electricity, which is sent to you from thousands of kilometres away so you can then heat an element, to heat the water. Coal-fired power stations are the biggest source of greenhouse gases. Gas is not perfect, but it is far better than burning coal.

• Switch to solar hot water. Consider the options of gas or electricity for boosting. Boosting electrically means you are encouraging coal-fired power stations, but it will save on the upfront costs. Yes you can sign up to GreenPower, but we need to make changes now and the current renewable energy input to the electricity grid is a very small and virtually symbolic. We must demand the use of technologies like geo-thermal power, solar power, wind and solar-thermal, but we should not pay a premium for this service.

• Install grid-connect solar power. But remember. You cannot store the power to use during the night.  You never actually use the power from the solar panels – you are always pumping this back into the electricity grid. View the electricity grid in this case as a big battery — you are helping charge this battery. Grid-connect systems have automatic switches in them to switch off the energy from the solar panels whenever the electricity grid is off. You will not be free from blackouts. A 1 kilowatt system in Queensland, may provide up to 5 kilowatt-hours per day in summer back to the electricity grid, therefore offsetting your electricity bill. Some Queensland households use up to 30 kilowatt-hours each day. A 1 kilowatt system however, is a good starting point and as you can see, it can reduce your electricity bills — just be aware of its limitations. A very efficient household can, on average, use as little as 2 kilowatt-hours per day!

• RECS. Cashing these in when you are buying a solar hot water system or grid-connect solar power system means you significantly save on upfront costs. But, holding onto them means you are encouraging the funding of more renewable energy projects. Once you cash them in, they are effectively used by high-polluting industries to continue polluting.

• Remember, electricity generators and retailers are in the business of making money. Making money from selling electricity. It is in their interest for us to consume more. It is in our collective interest to consume less.

Understanding current, with water

In Part 1, Understanding Power, we touched on current and the fact that it will vary depending on the appliance in use. Here we will use water as an analogy to help understand ways to become more energy efficient.

(Note for the technically minded: This is a very simplified analogy that is more suited to DC power (batteries) than AC. However it still serves as a good explanation)

Electricity is very similar to the water supply throughout your house, with all its taps and shower heads. The flow rate of the water (for example, the amount of water coming out of the tap each minute) is the current, and the pressure (the pump pushing the water through the system, either from a town water supply or the pump on your water tank) is the voltage. In fact the term current, is derived from this water-based analogy.

If the pressure is kept relatively constant by a pump, the flow of water is restricted by the resistance of the pipe. The resistance is related to the pipe’s diameter. Small pipe — less flow.  Remember in Part 1, when we discussed cable size and its relationship to current.

Reducing the flow

Water flow is completely stopped by closing a tap (or fixing a leaking tap) and so too is the current in an electrical circuit when a switch is turned off.

The rate of flow can be changed by altering the size of the tap outlet, or by using reduced flow devices, such as water efficient shower roses. Taps and shower roses are the water-based equivalent of electrical appliances and lights.

Restricting high rates of water flow, saves water. Restricting the use of high current electrical appliances, saves power. And leaking taps are the equivalent of leaving your DVD player in standby mode.

Heating water: the biggest consumer

Understanding the amount of current an appliance requires is important when making decisions about energy efficiency. For example, the biggest single current draw on your electricity system is an electric hot water unit.  They have their own tariff, and their own electrical circuit.

The average electric hot water unit, while heating, will consume 3.6 kilowatts at any one moment (they can be as large as 4.8 kilowatts). Relating this to your power meter readings and we see that running for just one hour, the hot water system will consume 3.6 kilowatt-hours. Over two hours it will have consumed 7.2 kilowatt-hours. Compare this to a 60 watt standard light globe switched on for two hours (0.12 kilowatt-hours), and the difference is very clear.

The demands of boosting solar hot water electrically

It should now become clear exactly why solar hot water is a smart first step in making your house more energy efficient. A high current device has almost been replaced by the heating power of the sun.

But it is also important to remember the boosting needs of solar hot water — when the sun doesn’t shine.

Boosting with electricity will, in most circumstances, require a connection to the electricity grid. Even if you have installed a grid-connect solar power system. The standard grid-connect system produces at best, slightly under 1 kilowatt of available power at any one moment in the middle of a sunny day. If your boosting element is 3.6 kilowatts, then it would require an extra 2.6 kilowatts, or a larger, more expensive array of solar panels and inverter to completely cover its demand for more current. But there’s a problem. Boosting would not be necessary during sunny days anyway, so therefore you are totally reliant on the normal electricity grid. Grid-connect solar power in this case becomes a way of offsetting the greenhouse-gas impacts of electrically boosting your solar hot water. Boost now, make up for it later.

This is why taking your electricity bill as the only indication of power consumption, can be misleading. Over a three month period the kilowatt-hours consumed from boosting your solar hot water system might appear insignificant. You may have turned the booster switch on one or two times at most. The fact remains, you still need the electricity grid, unless you are prepared to spend money on storing electricity in large battery banks, with large inverters capable of delivering suitably high current. Another option is to boost with gas. Read more about gas boosting here.

Reducing the demand on the grid

The longer we maintain our reliance upon the electricity grid, as more people build new homes, as the population increases, the more the grid will need to grow. The answer is, to not encourage bigger electricity grid networks, by reducing our use of high current appliances. Electricity grids impact not only at the point of power generation, but also through clearing vegetation, and the large, unsightly towers supporting high-voltage power lines.

By reducing energy hungry appliances and reducing the amount of time the smaller appliances are left on, our power consumption will reduce. We will become more efficient with our energy.

By now you are probably asking, where are the high energy devices in my house other than the hot water system. How do I know the power, or current they use? In the third and final part of this series we will look at better ways of measuring and managing power usage.

This is the first in a three-part series where we will look at the fundamentals of electricity use and why a better understanding of power is essential for better household energy efficiency.

Electricity is crucial to our daily lives. The power goes out after a storm, suddenly your cordless phone is useless, you can’t cook, you scramble around looking for a torch and wonder where you put your battery-run radio.

Something goes wrong and you call your local electrician. It’s technical, yet so fundamental to our lives. It must therefore be worth understanding in some way. Understanding electricity usage, is understanding that it is us, the consumers, who encourage more coal-fired power stations. Our appliances, our energy needs, have encouraged a dirty and inefficient form of energy.

Demystifying electricity and becoming more efficient in how we use it, is probably the most important contribution we can make to reduce our greenhouse-gas emissions.

Part 1 : Understanding power

Energy efficiency is the key to reducing household electricity costs and greenhouse-gas emissions. Solar hot water systems can dramatically reduce your electricity usage by removing a large proportion of your power needs. Grid-connect solar power can reduce your ongoing electricity costs as well. Both, in very different ways, supplement your existing electricity supply with energy from the sun. Something that is very abundant in a sunny country like Australia.

But, both solar hot water, namely electric-boosted systems, and grid-connect solar power, still require connection to the electricity grid. Even if you opt for a complete stand alone solar power system, efficient energy use is the most important factor. Understanding power, is the key to being more efficient.

To start, it helps to know exactly how much power you’re using. The simplest method is to take note of your electricity bill, although this has its limitations as it does not show when you are using the most power during the day or which are your most energy-hungry appliances.

Electricity bills show the total power you consume over a certain period, based on readings from your power meter. The most common type of power meter displays total power consumption, and is measured in kilowatt-hours.

What is Power?

The power meter measures the two components of power – voltage and current. Voltage, which in Australia is usually steady within a set range of 240 volts, and the current, which is the one component of power that varies. The power meter combines the voltage and current readings to show the energy, or power usage over time, in kilowatt-hours.

Power is directly related to current, and current is related to the appliances and lights in your house.  A 100 watt light globe for example, creates a higher current than a 60 watt globe.  An energy efficient light globe may be only 9 watts, therefore creating only a very small current. The voltage on each of the globes is the same, it is only the current that changes.

Time is an important factor too. A high current for a short period of time (such as a toaster), or a low current from an appliance in stand-by mode over a long period of time (DVD player), all add up. However, high current appliances create large demands on electricity networks. This is why electric hot water systems are on different tariffs. A different tariff so the power supply authority can control when they are on by injecting radio frequency pulses down the power lines. If every electric hot water system in every house turned on at once, electricity grids can collapse, resulting in wide-spread blackouts.

Appliances, such as air-conditioners, vacuum cleaners, toasters, electric jugs and coffee makers can each demand 1500 watts or more, and therefore create a high current. If you use electricity to heat air or water, then this is a good hint that high power usage is occurring, as this is a highly energy-intensive process.

Current is the reason your electricity cabling varies in size. The more current needed, the bigger the cable. The bigger the cable, the less resistance to current flow.

So we have established that your household power usage is related to current and time. That high currents create big demands on electricity networks. In Part 2 we will look at how current is related to water, and why this analogy can help us become more energy efficient.