Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). Renewable energy has seen a huge uptake in recent years, with advancements in technology meaning faster returns on investment and real long term savings. New technologies are now available to every home at increasingly affordable initial investments.
- Ice Thermal Storage
Thermal Storage Systems are due to take on a new prominence in the field of HVAC systems in order to compliment the increasing use of renewable generating methods such as wind and wave power.
The application of Ice Thermal Storage not only provides the opportunity to contribute to lower CO2 emissions and lower running costs for many HVAC Systems, but also provides a high degree of system resilience.
When applied to typical cooling situations, a portion of the cooling load, typically around 40%, is shifted to the ice storage. The daytime building cooling load is then satisfied by a combination of the liquid chilling equipment and the ice store. The ice store is then replenished overnight utilising off peak electricity.
Various operating strategies can be implemented depending upon the requirements of the building and the electrical power source. Where direct on site generation is a feature, this can lead to a zero carbon cooling installation.
Ice thermal storage has been now also been successfully applied to data centres to provide resilience in the event of chiller failure or maintenance.
Design & Operation
The Calmac tanks are of a cylindrical design to ensure that the tank receives equal pressure on all surfaces thereby ensuring the integrity of the tank. They are highly insulated to minimise standby losses and maximise efficiency. They can also be close coupled to form multiple modules.
The Calmac ice storage tanks operate on an internal melt principle with close coupled counterflow tubing ensuring that ice build temperatures and hence chiller operation is also maximised for efficiency.
Ice Storage systems can be either partial or full storage systems depending on the application. The chiller/Ice tank configuration can be either chiller lead or ice lead depending upon the required strategy. NCPI are able to offer a full design analysis utilising the bespoke Calmac “ICEPICK” software.
NCPI also offer a fully comprehensive CPD covering the technical aspects of ice storage systems.
The incorporation of ice thermal storage into a system can provide many benefits, including:
- Reduces peak demand at most critical time by up to 40%
- Can reduce CO2 emissions in the order of 10%
- Reduced chiller sizing, leading to lower operating costs
- Complimentary to renewable generating systems
- Additional LEED points awarded
- Low maintenance requirements.
Ice storage systems have been successfully installed in a variety of applications, including:
- Office Buildings
- Retail Stores
- Data Centres
- Educational Establishments
- Solar Energy Solutions
Solar energy solutions can harness energy from the sun, this can provide up to 80% of the energy required to heat your hot water. Solar thermal solutions can save you up to 50% on your annual heating costs, combine these solutions with a ground or air source heat pump and it is possible to have an almost completely renewable energy solution.
- Ground Source Heat Pumps
A ground source heat pump can be used to extract heat energy from the ground in winter and to transfer the heat into buildings. Equally it can be used to provide a very efficient mechanism for heat to escape from buildings down into the ground in summer.
A ground source heat pump provides a clean way to heat buildings, free of all carbon emissions on site. It can make use of energy stored in the ground to provide one of the most energy-efficient ways of heating buildings.
Ground source heat pumps are suitable for a wide variety of buildings and are particularly appropriate for low environmental impact projects.
They can be installed anywhere in the UK, using a borehole or shallow trenches or, less commonly, by extracting heat from a pond or lake. Heat collecting pipes in a closed loop, containing water (with a little antifreeze) are used to extract this stored energy, which can then be used to provide space heating and domestic hot water. Heat pumps can also be reversed in summer to provide cooling.
The only energy used by ground source heat pumps is electricity to power the pumps. Typically, a ground source heat pump will deliver 3 or 4 times as much thermal energy (heat) as is used in electrical energy to drive the system. For a particularly environmental solution, green electricity can be purchased.
Ground source heat pumps have been widely used in North America, Sweden, Germany and Switzerland for many years. Typically they cost more to install than conventional heating systems; however, they have very low maintenance costs and can be expected to provide safe, reliable and emission-free heating for over 20 years.
Ground source heat pumps work best with heating systems which are optimised to run at a lower water delivery temperature than is commonly used in radiator systems. As such, they make an ideal partner for underfloor heating systems.
- Save money; heat pumps are cheaper to run than direct electric heating
- Fully automated; they demand much less work than biomass boilers.
- Save space; there are no fuel storage requirements.
- Safe, there is no combustion involved and no emission of potentially dangerous gases and no flues are required.
- Less maintenance than combustion based heating systems
- Longer life than combustion boilers. The ground heat exchanger element of a ground source heat pump installation has a design life of over 50 years.
- Save carbon emissions; a heat pump produces no carbon emissions on site (and no carbon emissions at all, if a renewable source of electricity is used to power them).
- Provide cooling in summer, as well as heating in winter.
- A well designed ground source heat pump system is likely to increase the sale value of your property.
A ground source heat pump may not perform well unless it is incorporated in a good design encompassing the needs of the building, the use to which the building is being put and the local geology.
Contact us For more information on installation of ground source heating.
- Air Source Heat Pumps
Air source heat pumps absorb heat from the outside air and uses this energy to heat your home. This heat can be used to heat radiators, underfloor heating systems, warm air convectors and hot water. Heat Pumps can get heat from the air even when the temperature outside is as low as -15°C. Heat pumps do need electricity to run, but the heat they extract from the ground, air, or water is constantly being renewed naturally.
- lower fuel bills, especially if you are replacing conventional electric heating
- could lower your home’s carbon emissions
- no need for fuel deliveries
- can heat your home and provide hot water
- needs little maintenance
Heat pumps deliver heat at lower temperatures than conventional heating systems and over much longer periods. During the winter they may need to be on constantly to heat your home efficiently. You will also notice that radiators won’t feel as hot to the touch as they might do when you are using a gas or oil boiler.
- Fuel Cell
A Fuel Cell is an electrochemical device that converts chemical energy directly into electricity, in contrast to more conventional electric generation technologies such as natural gas turbines or fossil fueled boilers. Direct electrochemical conversion is environmentally attractive because of inherently low emissions, lower carbon intensity, as well as less noise and vibration because it is a “solid state” process.
While Fuel Cells have been known since the 1800’s, practical development began in the 1960’s under the impetus of the Gemini and Apollo space programs. Fuel Cells occupied a key role providing on board power and environmental support due to their high energy density to provide both heat and power, and because their by-product water was needed for drinking.
Fuel Cells have been in continuous development since the mid-1960’s incorporating substantial governmental and private industry funding. The major developers today have focused on four distinct technologies. The following chart outlines these technologies and the developers active in each category.
Fuel Cell Configuration
From a practical point of view, a Fuel Cell is much like a battery with one important difference. A battery essentially has a fixed amount of fuel and runs down when the chemical energy stored in it is consumed. In contrast, a Fuel Cell has its energy continually replenished and, thus, will continue to generate power as long as fuel is supplied.
Unlike a battery, hydrogen fuel is continuously supplied to the cell’s negative electrode called the anode. Concurrently, oxygen from ambient air is continuously supplied to the cathode or positive electrode. Like a battery, a Fuel Cell consists of two conductive plates separated by an insulating barrier containing an electrolyte.
Fuel Cell Usage
Depending upon the Fuel Cell technology incorporated into a power plant, the process converts from 30 to 49 percent of the fuel’s energy to electricity for customer or grid use. Also, between 30 and 40 percent of the fuel input can be recovered as useful thermal energy for site use, such as for water heating, space heating, and even air conditioning.
The Fuel Cell power plant is self contained, capable of fully automatic start-up and operation, and of maintaining an appropriate grid/customer interface under all conditions. Required Quarterly Maintenance can actually be done while the unit is operating. While the cell stack is an important part, it becomes just one of a number of other system components that operate together in a fully integrated, unattended manner.