Nicolas Liso Fabbri: RENEWABLE ENERGY TECHNOLOGIES: Types

Renewable energy technologies enable us to create electricity, heat and fuel from renewable sources.

Solar, wind, hydro, wave, heat-exchange, tidal, wave and bioenergy technologies are all powered by the sun, directly or indirectly.

Tidal and wave energy technologies are also powered by the moon. Geothermal technologies are powered by deep heat from the Earth's core.

Bioenergy technologies allow us to convert the solar energy stored in plants, food wastes, farm wastes, forest wastes, sewage, and algae into heat, electricity and fuel, using a variety of approaches.

These technologies allow us to heat and cool our buildings, generate electricity, and to travel by land, sea, and potentially also by air without generating dangerous greenhouse gases and other forms of pollution.

WIND

Wind power transforms the kinetic energy of the wind into electricity through rotation of the turbine’s blades. This creates a mechanical force that a generator converts into electricity.

In 2012, a wind energy assessment by the consulting company Garrad Hassan[2] found that due to the falling cost, wind energy is the most cost-effective renewable energy for large amounts of new generation in BC. The cost of turbines has fallen, and turbines optimized for sites with lower average wind speeds have produced a 34% increase in wind generation in these areas.

BC also has a wind turbine manufacturing company, Endurance Wind Power, based in Surrey, which manufactures 50kw and 225kw wind turbines for distributed wind power applications. Their induction-based turbines are sold across North America, the United Kingdom, Italy, and into an expanding global market.

According to BC Hydro, 19 of the top 20 most cost-effective wind energy sites in BC are in the Peace Region. A 2012 assessment indicates that wind energy resources outside the Peace region appear to be more competitive.

In rural areas, small wind turbines can be installed using BC Hydro's Net Metering Program (up to 100 kW), Fortis BC’s net metering program (up to 50 kw) or BC Hydro’s Standing Offer Program (up to 15 MW).

SOLAR PHOTOVOLTAIC

Solar energy is the cleanest, most abundant, renewable energy source available. The energy from the sun that hits the surface of the earth can be harvested into electrical energy, with great social and economic benefits.  Solar electricity is generated when photons (sunlight) land on the photovoltaic cells within a solar module. Photovoltaic cells can be used in a variety of applications ranging from single small cells that charge calculator or watch batteries, to systems using arrays of multi cell modules that power single homes, to large power plants covering many acres.  For the average consumer, the idea of generating energy into their home by adding a photovoltaic array to their roof is very appealing. These systems can offset the costs of electricity from the utility or export any excess energy back onto the grid (see Net Metering below).

GEOTHERMAL ENERGY

The Earth contains an incredibly vast amount of thermal energy. Geothermal energy uses the escaping heat from Earth’s core as a means to heat water to produce steam and use the pressure and produce electricity. After the steam condenses, the water may be pumped back down to be reused.

Geothermal energy may also refer to the use of underground water that, despite being at temperatures above boiling point, remains a liquid due to the high pressure of being deep beneath the surface. This water, when brought to the surface, immediately turns to steam and can be directly used to turn turbines.

BC Hydro has identified 16 prospective geothermal sites in the province, with the six most likely prospects having an estimated geothermal potential of over 1,000 megawatts collectively. Others estimate the provinces potential to be approximately 3,000 MW of capacity.

The best prospect for immediate development in BC is the South Meager Geothermal Project located 55 km north of Pemberton. South Meager, with average temperatures of 260 degrees Centigrade, has been assessed as having a potential generating capacity of up to 100 MW (enough to supply 80,000 homes).

HYDRO

Hydroelectricity is the production of electricity through the utilization of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity generation.[1]

British Columbia is powered predominantly by 21 large scale hydroelectric facilities and 7 small scale hydroelectric facilities, generating a staggering 10,829 Megawatts of clean, emissions free electricity powering 1.9 million homes across BC.[2]

LARGE SCALE HYDRO

Large hydroelectric facilities dam rivers, store the water in a reservoir and then release it as needed to generate electricity. They use the gravitational potential of water held in the reservoir to drive a water turbine and generator when released to flow through the dam.[3] The amount of power in the water depends on the volume and the difference in height between the source of the water and the water’s outflow. Large scale hydroelectric dams’ ability to store ‘firm energy’ for release at peak demand and during periods when water flows are lower make hydroelectric facilities extremely attractive to a power utility.

The biggest concern with any dam project is always the land that must be flooded, bringing the loss of ecosystems, species, forests, farmland, and sometimes (in China) entire villages or towns. The damming of any river creates an obstacle for migrating fish, especially salmon. Large dams are often insurmountable; smaller dams have fish-ladders to help the fish migrate. Large dams do generate methane emissions from the degradation of biological material left in the reservoir, but the amount is countered by the emissions avoided not using fossil fuels to generate electricity.

SMALL SCALE HYDRO

Small scale hydroelectric refers to run-of-river facilities and hydroelectric plants that use the kinetic energy of a fast flowing river. Substantial flooding of the upper part of the river is not required for run-of-river projects as a large reservoir is not required. As a result, people living at or near the river do not need to be relocated and natural habitats and productive farmlands are not wiped out.[4]

There are 51 Run-of-River projects operating in BC. Although there are countless rivers in the province, not all are suitable for a run-of-river facility. Potential sites must have cost-effective transmission access, undergo a comprehensive environmental assessment, meet government guidelines and regulations, and be commercially viable.