The Alternative Energy blog – green renewable alternative energy


July 29, 2009

Investments in Alternative Energy are Rising

Category: wind energy – Tags: , – 12:54 pm

Venture capitalists in the USA are heading back into the alternative energy sector. Investments in the sector have increaesed by 73 percent in the last 3 months.

A report issued today by Ernst & Young LLP says venture capital investment in the clean-technology sector totaled about $572 million from April to June.
That’s still far less than the money invested during the second quarter of 2008, a big year for alternative energy, but suggests that the worst may be over for solar, wind geothermal and other cleantech businesses.

July 19, 2009

How to use solar panels to heat a swimming pool

To heat your swimming pool, you can use a combination of solar pool collectors and thermal arrays.

Thermal arrays can be used to heat water tanks,. These panels collect the sun’s heat. The heat is then run through a piping system inside that’s filled with water or antifreeze.
Thermal pool covers or solar collector are made of special solar rings that can heat the pool’s temperature five degrees. Solar collectors pump the pool water through a piping system like that of the thermal array. The water absorbs the heat and is returned to the pool 10 degrees hotter.

With a combination of both thermal pool covers and thermal arrays, a pool can be heated 15 degrees.

July 17, 2009

Marine Turbines

Category: wave energy – Tags: , , , , , – 1:18 pm

Marine turbines are a great hope for renewable green power.

One of the most promising marine energy technologies is the tidal turbine, which was advocated in Manchester by Peter Fraenkel of Marine Current Turbines (MCT). These devices act like underwater windmills, with blades that rotate as the tide flows through them. Tidal turbines create large amounts of power in those countries with very fast-flowing tidal streams – such as the UK and Canada – and in the future similar devices could be used to extract energy from deep ocean currents such as the Kuroshio in north-west Pacific.

Compared to wind and solar energy, tidal generation has the advantage of predictability. Being driven by the gravitational pull of the moon and sun, as opposed to the weather, their timing and strength is known in advance to a high level of certainty. A further advantage is the high energy density of the tides. With as much as a thousand tonnes of water passing through a turbine’s blades in a single second, a relatively small device can create a relatively large amount of electricity.

Producing devices robust enough to withstand these forces is a formidable engineering challenge, but MCT’s flagship device – the SeaGen – has already been proven to work on a commercial scale. Positioned in Strangford Lough, Northern Ireland, the first SeaGen turbine has generated more than 100 megawatt hours of electricity.

July 15, 2009

UK: Wave Power Boost

Category: wave energy – Tags: , – 7:40 pm

An extra £8m is to be invested developing wave power at Orkney’s marine energy centre. It is part of the UK government’s plan to cut carbon emissions and generate more renewable energy over the next ten years. The announcement was made at Edinburgh based Pelamis wave power by Jim Murphy, the secretary of state for Scotland.

July 14, 2009

Build your own solar panels

Category: solar panels, solar power – Tags: , , , – 8:44 pm

This is a great book that tells  you how to build your own solar panels and save thousands on your home energy costs.

Build your own solar panels.


solar panels, DIY, alternative home energy

Cut back on wind farms and build nuclear plants says UK business group

UK: The CBI has called on the UK government to scale back on “overambitious” wind power and boost the role of atomic energy and coal.

read more

Solar power from deserts could power the whole of europe

Category: solar power – Tags: , , – 8:06 pm

Concentrating solar power (CSP) involves using arrays of mirrors to focus large amounts of sunlight onto a small area. This creates extremely high levels of heat, which can be converted into electricity using a steam turbine or Stirling engine – or stored in tanks of molten salt to provide power at night or on cloudy days. The mirrors can be parabolic troughs or giant dishes. Alternatively, a large number of sun-tracking flat mirrors can direct sunlight to the top of a so-called “power tower”.

According to advocate Gerry Wolff, coordinator of the British wing of the Desertec project, the world could slash emissions and improve energy security by putting large CSP plants in the Sahara and other desert regions. Wolff estimates that less than 1% of the world’s deserts would provide enough space to produce as much electricity and the world currently consumes. An area of just 139km by 139km could match current EU power consumption. As a bonus, the waste heat from the electricity generation could be used to provide desalinated water to dry regions, and the shade of the mirrors could facilitate horticulture in areas usually too hot to support it.

Electricity from the deserts could be transferred to population centres thousands of miles away using high-voltage direct-current cables. Similar cables could connect existing grids to large wind farms, hydroelectric stations and geothermal plants, creating continent-sized “supergrids” that would provide copious quantities of renewable electricity as inexpensively and reliably as possible.

Geopolitical issues with the Desertec scheme – such as North African control of European electricity – remain to be resolved, but there are no insurmountable technical barriers. CSP is a proven technology, with plants up and running in the US, Spain and other regions.

Guardian – Manchester Report july 2009

July 7, 2009

Home Solar Panels – Save You Money

Great article in the UK’s Guardian newspaper proving that even in rainy Britain home solar panels are a great investment.

The Rewards of Solar Panels by Ashley Seager
We live in an old terraced house on a cloudy, rainy island. Yet the solar photovoltaic (PV) panels on our roof, put up two years ago, are supplying around 90% of all the electricity used by my family.

The initial cost is high, but don’t let that put you off. Two key developments in recent months have made it worth considering solar PV panels.

One is that a government incentive for PV doubled on 1 April and the other is that interest rates on many savings accounts have dropped to about 0.1%, meaning it is time your money worked harder.

And don’t be deterred by the idea Britain doesn’t get enough sunshine. In fact, solar radiation here is remarkably consistent and only around one third less than southern Italy or Spain. I have just come to the end of my second year with a solar PV system on my roof and it has been a great success.

We have a 3kW peak system (about 4m by 3m) on the roof. It produced 2,703kW hours (kWh) in its second full year (to 5 April), only 1% lower than the 2,730 kWh it produced in the first year, and that in spite of a lousy 2008 summer.

That was about 80% of the 3,500 kWh we used, and our usage was up because we had builders do some underpinning, which meant lots of kettles and cement mixers on.

The previous year we – a family of four –

used 3,000 kWh, so the solar system produced 92% of our needs, a figure we expect to return to in the coming 12 months.

The panels, made by Kyocera of Japan, come with a 25-year guarantee and should last a lot longer than that. What you effectively do when you buy a solar PV system is pre-buy decades of electricity at today’s price, thus shielding you from price rises. One great thing about a PV system is that it is “fit and forget” with little or no maintenance or noise. And they don’t have to go on a directly south-facing roof –

ours points south-east and works very well.

So how do the figures work out? Well, buying 3,000 kWh of electricity normally would cost around £420, based on 14 pence/kWh with npower, our supplier. We end up saving almost £400 of that by producing nearly all our own.

On top of that, we were getting payments under the government’s Renewable Obligation Certification (ROC) scheme of around £35 per megawatt/hour, rounded to the nearest whole one. So that is £105, putting us about £70 in the black for the year.

Since 1 April, that ROC payment has doubled to £210, putting us about £175 in the black. That compares with £420 in the red without the panels –

a gain of almost £600 a year.

Indeed, the system means that, with a condensing boiler, we are now down to only about £30 a month to heat and light our property while our carbon emissions are very low. So what about the investment yield? The system cost £17,000, for which we got a 50% grant, making £8,500. With a return of £600, that’s around 7%. It’s not taxed, so is equivalent of about 9% for a basic-rate taxpayer and 11% for a higher-rate taxpayer. You’d struggle to do better buying junk bonds and this stuff is certainly not junk!

Moreover, that gives you a crude payback period of only 10 years, not the 100 years that some critics have claimed.

Ah, you say, but that 50% grant is no longer available, the maximum is £2,500. True, but systems have come down in price since we installed ours, so your post-grant price for a system like ours would be around £12,000 now. The £600 saving gives a return of 5% (or 7% or 8.5% gross –

not bad when compared with just about any other kind of investment these days).

And, if you are lucky enough to be on a tracker mortgage that is close to 0%, you could add on to your mortgage and it would really pay to invest in a PV system.

That 5% yield is likely to improve –

next April, the government plans to introduce a so-called feed-in tariff (FIT) when you get paid an above-market price for every unit of electricity fed into the grid.

The ROC system gives you the equivalent of about 27p-28p per exported unit, but the FIT could well be higher than that. It is not clear how the FIT will work but it will probably replace the ROCs and the £2,500 grant.

And the yield will likely improve further as electricity prices are almost certain to increase faster than inflation over the next three decades.

Some critics say PV is an expensive way to save carbon, but system costs are plummeting as world supplies of silicon, from which PV is made, have shot up. Moreover, global panel production has rocketed in response to FITs in other countries. A PV system in Germany, for example, is about half the UK price –

no wonder the Germans have 300 times as many PV systems installed as we do. But even with the higher UK prices, it is worth investing in a PV set-up.

Ah, but what if I move house, you ask? Well, I am convinced that a system that saves you £600 a year and protects you against future rises in electricity costs will add to the value of your house. How could it not?