Questions tagged [energy]
Energy is defined as the amount of work that can be performed by force, measured in Joules. Energy is Power over Time. This is a poor tag to use. Please consider if your question relates to Energy as defined in physics, not as a synonym for Power or capacity.
491
questions
3
votes
3
answers
168
views
Understanding the flux linkage in transformers
I am having difficulty understanding the concept of flux linkage in transformers, particularly how the secondary winding receives its flux when all the flux is said to be confined to the iron core. I ...
- 33
0
votes
0
answers
17
views
energy flux density vs distance
I am looking for a formula for the figure given below. The Figure shows distribution of the energy flux density of electromagnetic radiation at a height of 2 m from the earth's surface in the area of ...
- 3
1
vote
3
answers
97
views
Best way to calculate Energy used in a circuit
I'm trying to figure out how to calculate energy consumed through my circuit. I can read the current and see the voltage, can obviously calculate the instant power, but I'm fairly certain that I don't ...
- 151
0
votes
0
answers
21
views
Estimate transient power of crowbar circuit
I am designing a crowbar circuit and for this circuit it is important that the maximal transient energy that goes through the circuit before the fuse trips stays below a certain limit. The setup of ...
- 11
0
votes
0
answers
19
views
Getting Energy values from the Allegro ACS37800
I am currently using the Allegro ACS37800 IC to monitor power, from what I found on the datasheets and from the internet this IC is capable of calculating the voltage, current, and power. I actually ...
- 1
0
votes
0
answers
8
views
Will a whole house surge protector save energy? [migrated]
I'm considering having an electrician install a whole house surge protector. The house gets 200 amps from the grid. The surge protector would protect appliances and the new electric car (a Leaf). Some ...
- 101
0
votes
0
answers
64
views
Construction of a Lagrangian function for a circuit
I was reading the paper "Introduction to quantum electromagnetic circuits", by U. Vool and M. Devoret and I am stuck in the construction of a Lagrangian function for the example LC circuit ...
- 1
0
votes
1
answer
108
views
What types of power rail are there in an integrated circuit?
I understand that power rails provide the energy required for a circuit to function. Intuition tells me there must be at least two types of rail, one providing power and another taking it away.
But I ...
- 301
3
votes
4
answers
373
views
Power consumption based on voltage and current
I'm a little confused of which value of the voltage to consider for calculating the power consumption.
Here is the scenario of my voltage and current drawn over a period of time.
Vmax = 100 V
...
- 33
0
votes
2
answers
96
views
How can energy be stored in a magnetic field?
A magnetic field can be thought of a vector field of force on electrons. Basically this can be thought of a some area that attracts or repels electrons.
It is said that inductors are able to "...
- 197
1
vote
2
answers
81
views
Power and energy of pumped hydro versus grid scale batteries
A company is proposing a pumped hydro system where they state on their website as “capable of producing up to 335 MW of electricity with around 8 hours storage”.
The same company is proposing a ...
- 11
0
votes
3
answers
128
views
Are two capacitors connected together considered to be parallel or series?
If both ends of two capacitors are connected to each other but in such a way that the positive end of one capacitor is connected to the negative end of another capacitor, do we say that the capacitors ...
- 51
1
vote
1
answer
85
views
Power and energy calculation of square (or rectangular) wave signals
I have to calculate the power of my square (actually rectangular :D) wave signal, and then the energy of it. I have amplitude, current, duty cycle, and frequency parameters.
For example:
Amplitude: 2....
2
votes
1
answer
108
views
Proper burden resistor CT clamp
I'm trying to figure out what the proper burden resistor I should use, but the information I'm reading from OpenEnergyMonitor answer for the proper resistor values doesn't match what I was expecting.
...
- 21
0
votes
0
answers
69
views
Energy-delay-product vs. Joule to watt conversion formula
I am currently on my master's doing an assignment, and I am in this point in time extremely confused and I was wondering about this, quite possibly, stupid question. I am just too afraid to ask at ...
1
vote
1
answer
77
views
For how long would a 12V 8Ah C20 battery last by heating 100 resistive Kanthal (A1) 20awg 30 cm long wires to 130 ºC in half a second?
Well, I want to heat up 100 wires with 20cm of length each made of Kanthal (A1) with 20 awg gauge (0,8mm/0.03inch diameter and 0.817 ohms/in) to 130 ºC from room temperature of 30 ºC continuously. And ...
- 182
4
votes
1
answer
183
views
Convert watts (collected at set interval over set time period), into kWh
I have an energy monitor which collects the power usage (W) of a device, every 3.11 seconds. If I want find the total energy consumption (kWh) of the device over a set time period, how would I do it?
- 145
4
votes
1
answer
184
views
Does a parallel air gap increase or decrease maximum energy stored in magnetic field of an inductor?
I understand that a serial air gap increases the amount of energy that can be stored in an inductor.
The reasoning is as follows: according to Gauss's law for magnetism, divergence of B-field is zero. ...
- 1,503
0
votes
0
answers
32
views
Microwave oven approximate efficiency [duplicate]
I just made popcorn in the microwave and I wonder how much energy my popcorn absorbed and how much energy was consumed by oven. It was 90g of corn and butter (kind of...) and it needed 800W for 3 ...
- 5,856
0
votes
1
answer
70
views
Big differences between AC and DC measurements
I am conducting some electricity measurements with Tinkerforge. To be more precise, I am measuring the energy consumption of a RPi 4, and for that I use two Tinkerforge bricklets.
The first one, ...
0
votes
1
answer
41
views
Is this method of proving energy is conserved in an LC oscillator correct?
Assuming no energy loss due to heat or EM waves
$$U=\frac{Q^2}{2C} +\frac{LI^2}{2}$$
differentiating both sides with respect to time,
$$\frac{dU}{dt}=\frac{QdQ}{Cdt}+IL\frac{dI}{dT}$$
but we know that ...
4
votes
1
answer
288
views
Power loss in a capacitor vs inductor
Is there are a general rule of thumb if one of these stores energy more efficiently than the other?
When properties are approximateily comparable, are energy losses bigger with a coil or with a ...
- 43
0
votes
0
answers
32
views
When calculating the energy delivered by a pulse in an oscilloscope, what is the uncertainty in the timestep increment? [duplicate]
I am trying to calculate the energy delivered by a short electrical pulse. I am using an oscilloscope to capture the waveform and then exporting it to a CSV file. My scope took measurements at a rate ...
0
votes
2
answers
191
views
How do I convert generated cooling capacity in kW to kWh?
I have to program a relatively simple program so I can display values on dashboard representing the part kWh a system is responsible for generating. This will be represented as a percentage.
I have a ...
- 1
-3
votes
1
answer
88
views
Alternatives for batteries for energy storage [closed]
If it is not the indicated Stack App, let me know, please. I don't really know if this topic is about chemical stuff because of batteries composition or just a electronic energy problem.
I've been ...
2
votes
1
answer
82
views
Why does air conditioner power draw fluctuate during the day?
My air conditioner is controlled by a thermostat like most are. When the set temperature is exceeded, the system turns on the air conditioner using the R and Y wires of the controller. As I ...
- 41
3
votes
0
answers
100
views
Identify chip labelled SC1186E
I am trying to identify the manufacturer and function of, and hopefully locate a data sheet for, this chip labelled SC1186E. It is in a three-phase power meter, so my guess is, that it is an ADC front ...
- 51
6
votes
5
answers
5k
views
Confused about MW to MWh conversion
I have various datasets of energy production in MW.
I need to present everything in MWh. I need to know if my data is already by the hour (logging a value for each hour of each day of an entire year), ...
- 89
0
votes
3
answers
273
views
How to convert kWh to half hour time series?
I have an energy reading of 50 kWh. The duration of this reading is from 09:00 to 10:30 (or 1.5 hours).
If I want to make a 30-minute time series, how could I convert 50 kWh into 3 half-hourly ...
- 1
-1
votes
1
answer
107
views
Calculate the power consumption
I have project put the ESP32-S2 in active mode for 10 second and then go to modem-sleep mode. I want to compute the power consumption for the active mode. According to this, the ESP32-S2 current ...
- 101
1
vote
4
answers
133
views
Matching generation and consumption in renewables
To balance power generation and consumption, traditional power plants such as thermal and hydro have governors that regulate the steam/water that flows into the turbine.
The energy that renewables ...
- 81
2
votes
2
answers
86
views
Which topology should I use for energy harvesting
I am making a energy harvester design but am confused which of the following circuit should I use to amplify and filter my harvested voltage. The first topology is the synchronous switch harvesting on ...
- 21
6
votes
1
answer
533
views
What role do electrons play in a circuit other than establishing an electric field?
In a simple electric circuit consisting of a load (such as a filament lamp) and a power source (a 5 V battery), when the switch is turned on the electrons experience a "displacement" which ...
- 183
1
vote
3
answers
68
views
Can V²/R be used to find energy of a DC transformer pulse?
A person I am working with is trying to determine the efficiency of a pulse transformer and I am confused by the procedure.
We know the input energy because a capacitor is discharged across the ...
0
votes
2
answers
163
views
Why does AC current go both ways but energy in only one way?
We all know the Alternating Current has no definite direction such as forwards or backward but goes both ways, so my question is that as AC flows both ways why does the electrical energy flow only one ...
- 183
0
votes
3
answers
85
views
Open circuit photodiode energy
Where does a photo-diode use the energy it collects from light and other EM waves when not loaded? Does it dissipate it as heat, reflect it or something else?
- 101
-4
votes
5
answers
169
views
Doesn't the law of conservation of energy invalidate Ohm's law?
Imagine I have a power supply supplying a 12 amp AC current of 12 volts. The resistance of the circuit, consisting of only a copper wire and a resistor, is 1 ohm.
In this instance Ohm's law holds true:...
0
votes
1
answer
83
views
Mismatched rating in Ah and Wh. Why is that?
My question concerns the apparent mismatch between the Wh rating and the Ah rating often found on batteries.
On one of my batteries the label says:
12V Leisure Battery TR350 TUDOR EXIDE DUAL 80Ah, ...
- 11
0
votes
3
answers
66
views
A machine's energy consumption per product
I need to find the energy consumed per product.
Let's say we have product cycle of 10 seconds.
The machine reports the average wattage of each second.
...
- 3
2
votes
4
answers
1k
views
A capacitor charge time - two methods two different answers
I am a bit puzzled and ask for your help about the following:
A theoretical capacitor of 100 F is being charged with a constant power source of values V = 50V, I = 50A, ESR of capacitor = 5 mohm
To ...
- 33
0
votes
2
answers
215
views
Battery capacity and parallel vs. series battery connections
Say you have 4 200 Ah 12 V batteries connected in parallel, this as I’ve come to learn increases the amp-hour value and not the voltage, and say you have another system same as that but connected is ...
- 3
5
votes
6
answers
2k
views
Why can't current change instantaneously in a given inductor?
I know the mathematical reason behind this. Given the inductor I-V characteristic we know that:
I understand mathematically that a function which is differentiable must be continuous, but what is the ...
- 163
0
votes
1
answer
57
views
How is energy conserved in an LC tank with voltage offset?
Consider an ideal LC tank oscillator offset by an ideal battery*:
The core question is this: is the energy balance here maintained by the charge-voltage relationship of the battery? Energy seems to ...
- 131
-3
votes
1
answer
66
views
Energy cost conversion [closed]
If electricity costs $0.06 per kilowatt-hour and is used for electric heating with an efficiency of 100%, what is the equivalent price of natural gas per gigajoule if it can be burned with an ...
- 847
0
votes
1
answer
182
views
Magnetic energy harvesting with a current transformer
I am planning to design a magnetic energy harvesting circuit with a current transformer (CR8349-1500) to charge a super capacitor.
Load current rating is 0 to 35 amperes. From the current transformer ...
- 87
0
votes
1
answer
240
views
Convert kWh during a 1 hour period to average 15 min kW output
If I have a photovoltaic system that outputs 100 kWh from 1PM - 2PM on a given day and I am trying to figure out what the average 15 minute kW would be during that time period, would that be equal to ...
- 1
0
votes
1
answer
82
views
How to calculate watt hours gained charging battery?
I need an estimate of how many watt hours a battery has gained after charging to a certain number of volts.
With a 12 V, 50 Ah lead-acid car battery, charged from 12.5 V to 13.0 V, is it as simple as ...
- 11
0
votes
3
answers
219
views
How is a sleep mode of a micro-controller realized? [closed]
How can a micro-controller save energy?
What does it mean if the micro-controller throttles its CPU?
How can a micro-controller "turn off peripherals" that are not needed to save energy?
I ...
1
vote
2
answers
46
views
What does "highest ionizing energy deposition" mean?
I am looking for how to compute the thickness of shielding materials and have found the following research:
ISNPS Technical Report ISNPS-1-2013 Tai and El-Genk.doc (unm.edu)
The report is mentions the ...
- 227
0
votes
1
answer
126
views
How to measure energy usage from a 12V battery over a daily pump cycle
I am working on a project right now where two different DC water pumps are being powered by a single 12V DC battery. I am trying to do some performance testing to find how much energy from the battery ...
- 1